=Aluminum=, a metal which does not occur in nature in the free state,
but for the most part in combination with silica, as a silicate of
aluminum, in clay and many minerals. As extracted from clay by a series
of very difficult chemical operations, it forms a white metal, very
ductile and malleable, and susceptible of a high polish. On account of
its lightness, aluminum is highly valued; it forms excellent alloys.
_Bauxite_ (aluminum hydrate) is the only ore. It is mined in France,
Ireland, Austria, Arkansas, Alabama and Georgia, and is refined by
electric processes. It is used largely as an addition to iron and steel,
preventing bubbles and waste in castings; in electrical work, and for
purposes where a light, strong metal is necessary, as in certain
machinery, hulls for small boats, etc. Refineries are located in
Switzerland, France, Great Britain and United States.
_Cryolite_ (fluoride of aluminum and sodium), a mineral mined only in
Greenland, was formerly used as an ore but is now utilized in the
manufacture of alum and soda.
_Alum_ (a sulphate) is made from cryolite or clays.
_Corundum_ (aluminum oxide) is, next to the diamond, the hardest natural
mineral. Canada, North Carolina, Alabama and India have mines of
corundum. Emery is produced chiefly in Greece and Asia Minor. Corundum
and emery are powdered for use as abrasives in wheels, sharpening
stones, polishing powder and cloth.
_Emery_ is an impure form of corundum.
_Feldspar_ is a silicate of aluminum with other metals. It is mined in
Canada, Pennsylvania, Connecticut, New York, Maine and Norway, and
ground up for use in pottery making.
_Clay_ is chiefly silicate of aluminum and other metals. _Kaolin_ is its
purest form. The properties of clay vary with its composition, as china
clay, fire clay, pipe clay, brick clay. Clays are found in all parts of
the world as a result of the decomposition of other rocks.
The location of manufacturing centers of pottery of all kinds and of
bricks, is dependent on clay deposits. In pottery making, Ohio, New
Jersey and Pennsylvania lead the United States. Abroad, fine china is
made in France, Germany, Austria, England, Japan, and China.
=TABLE FOR THE IDENTIFICATION OF COMMON MINERALS; THEIR SCIENTIFIC AND
COMMON NAMES AND CHIEF CHARACTERISTICS=
+-------------------+---------------+---------------+------+----------+
| =Name of Mineral= | =Common Name= | =Composition= |=Hard-| =Lustre= |
| | | | ness=| |
+-------------------+---------------+---------------+------+----------+
|=Amphibole.= |... |Silicate of | 5-6 |Glassy to|
|(_ăm´fĭ-bōl_) | |magnesium, | |dull. |
| | |calcium, alumi-| | |
| | |num, iron, etc.| | |
| | | | | |
|=Arsenopyrite.= |Mispickel. |Sulphide and | 6 |Metallic. |
|(_är´sĕn-ō-py̆r´īt_)| |arsenide of | | |
| | |iron. | | |
| | | | | |
|=Barite.= |Barytes. Heavy |Sulphate of | 3 |Glassy to |
|(_bā´rīt_) |spur. |barium. | |stony. |
| | | | | |
|=Biotite.= |Black Mica. |Hydrous sili- |2-1/2-|Glassy to |
|(_bī´ō-tīt_) | |cate of alumi- | 3 |almost |
| | |num, potassium,| |metallic. |
| | |magnesium and | | |
| | |iron. | | |
| | | | | |
|=Calcite.= |Lime. Calespar.|Carbonate of | 3 |Glassy to |
|(_kăl´sīt_) | |Calcium. | |earthy. |
| | | | | |
|=Chalcocite.= |Copper Glance. |Sulphide of | 3 |Metallic; |
|(_kăl´kŏ-sīt_) | |copper. | |dull when |
| | | | |impure or |
| | | | |tarnished.|
| | | | | |
|=Chalcopyrite.= |Copper Pyrites.|Sulphide of | 4 |Metallic. |
|(_kăl´kō-pĭr´īt_) |Fools gold. |copper and | | |
| | |iron. | | |
| | | | | |
|=Copper.= |... |Native metallic|2-1/2-|Metallic. |
| | |copper. | 3 | |
| | | | | |
|=Corundum.= |... |Oxide of alu- | 9 |Glassy. |
|(_kō-rŭn´dŭm_) | |minum. | | |
| | | | | |
|=Epidote.= |... |Basic silicate | 6-7 |Glassy to |
|(_ēp´ĭ-dōt_) | |of calcium, | |dull. |
| | |aluminum and | | |
| | |iron. | | |
| | | | | |
|=Fluorite.= |Fluor Spar. |Calcium | 4 |Glassy. |
|(_flōō´or-īt_) |Fluorine. |fluoride. | | |
| | | | | |
|=Galenite.= |Galena. Lead. |Sulphide of | 3 |Metallic. |
|(_gȧ-lē´nīt_) | |lead. | | |
| | | | | |
|=Garnet.= |... |Silicate of |6-1/2-|Glassy to |
| | |various ele- |7-1/2 |resinous. |
| | |ments: calcium,| | |
| | |aluminum and | | |
| | |iron are | | |
| | |commonest. | | |
| | | | | |
|=Gold.= |... |Native metallic|2-1/2-|Metallic. |
| | |gold with a | 3 | |
| | |little silver, | | |
| | |copper, etc. | | |
| | | | | |
|=Graphite.= |Black Lead. |Carbon. | 1-2 |Metallic |
|(_graph´īt_) |Plumbago. | | |to dull. |
| | | | | |
|=Gypsum.= |... |Hydrous sul- |1-1/2-|Pearly, |
|(_jĭp´sŭm_) | |phate of | 2 |silky, |
| | |calcium. | |vitreous, |
| | | | |dull. |
| | | | | |
|=Halite.= |Rock salt. |Chloride of |2-1/2 |Glassy. |
|(_hā´līt_) | |sodium. | | |
| | | | | |
|=Hematite.= |Red oxide of |Oxide of iron. |5-1/2-|Metallic |
|(_hēm´ȧ-tīt_) |iron. | |6-1/2 |to earthy.|
| | | | | |
|=Limonite.= |Yellow oxide of|Hydrous oxide | 5- |Dull, |
|(_lī´mŏn-īt_) |iron. |of iron. |5-1/2 |silky, |
| | | | |varnish- |
| | | | |like. |
| | | | | |
|=Magnetite.= |Magnetic iron |Oxide of iron. |5-1/2-|Metallic |
|(_mag´net-īt_) |ore. | |6-1/2 |to dull. |
| | | | | |
|=Malachite.= |... |Hydrous carbon-|3-1/2-|Silky to |
|(_măl´ȧ-kīt_) | |ate of copper. | 4 |dull. |
| | | | | |
|=Muscovite.= |Mica, isin- |Hydrous sili- | 2- |Glassy. |
|(_mŭs´ko̱vīt_) |glass. White |cate of potas- |2-1/2 |Pearly on |
| |Mica. |sium and alu- | |cleavage |
| | |minum. | |faces. |
| | | | | |
|=Orthoclase.= |Feldspar. |Silicate of | 6 |Glassy to |
|(_ôr´tho̱-klās_) |Potash. |potassium and | |stony. |
| | |aluminum. | | |
| | | | | |
|=Pyrite.= |Pyrites. White |Sulphide of | 6- |Metallic. |
|(_pĭr´īt_) |iron. Fools |iron. |6-1/2 | |
| |gold. | | | |
| | | | | |
|=Pyrolusite.= |... |Oxide of | 1- |Metallic |
|(_pĭr´o̱-lū´sīt_) | |manganese. |2-1/2 |to dull. |
| | | | | |
|=Pyroxene.= |... |Silicate of | 5-6 |Glassy to |
|(_pĭr´ŏks-ēn_) | |magnesium, | |dull. |
| | |calcium, alu- | | |
| | |minum and iron.| | |
| | | | | |
|=Quartz.= (Pheno- |... |Oxide of | 7 |Glassy. |
|crystalline). | |silicon. | | |
| | | | | |
|=Quartz.= (Crypto- |... |... | ... |Dull to |
|crystalline). | | | |earthy. |
| | | | | |
|=Serpentine.= |... |Hydrous sili- | 4+ |Wax-like, |
|(_sēr´pēn-tīn_) | |cate of magne- | |silky, |
| | |sium and iron. | |earthy. |
| | | | | |
|=Siderite.= |... |Carbonate of |3-1/2-|Glassy to |
|(_sĭd´ēr-īt_) | |iron. | 4 |earthy. |
| | | | | |
|=Sphalerite.= |Blende, Jack |Sulphide of |3-1/2-|Resinous |
|(_sfāl´ēr-īt_) |Rosin zinc, |zinc. | 4 |to nearly |
| |zinc, etc. | | |metallic. |
| | | | | |
|=Stibnite.= |... |Sulphide of | 2 |Metallic. |
|(_stĭb´nīt_) | |antimony. | | |
| | | | | |
|=Talc.= |Talcum. |Hydrous sili- | 1- |Waxy to |
|(_tălk_) | |cate of mag- |1-1/2 |dull. |
| | |nesium. | |Pearly on |
| | | | |cleavage |
| | | | |faces. |
| | | | | |
|=Tetrahedrite.= |Gray copper. |Sulph- | 3- |Metallic. |
|(_tet´ra-he´drīt_) | |antimonite of |4-1/2 | |
| | |copper. | | |
| | | | | |
|=Tourmaline.= |Schorl. |Silicate of | 7- |Glassy to |
|(_tōōr´mȧ-lĭn_) | |boron and |7-1/2 |resinous. |
| | |various other | | |
| | |bases varying | | |
| | |with the | | |
| | |variety. | | |
| | | | | |
|=Zoisite.= |... |Silica, alumi- | 6 |Pearly. |
|(_zois´īt_) | |na, lime, per- | | |
| | |oxide of iron, | | |
| | |water. | | |
+-------------------+---------------+---------------+------+----------+
+-----------------+--------------+-------------+-----------------------+
|=Name of Mineral=| =Color= | =Streak= | =Cleavage or |
| | | | Fracture= |
+-----------------+--------------+-------------+-----------------------+
|=Amphibole.= |Black or light|White. |Perfect in two direc- |
| |to dark green.| |tions at angle of 124°.|
| | | | |
|=Arsenopyrite.= |Silver, |Black. |Good in two directions |
| |yellowish, or | |at an angle of 112°. |
| |light grayish | |Not evident on fine |
| |white. | |grained material. |
| | | | |
|=Barite.= |White, yellow,|White. |Perfect in one direc- |
| |blue or brown.| |tion; two other good |
| | | |cleavages at right |
| | | |angles to the first and|
| | | |at 101° with each |
| | | |other. |
| | | | |
|=Biotite.= |Black or dark |White. |Very perfect in one di-|
| |brown. | |rection, yielding thin |
| | | |sheets. |
| | | | |
|=Calcite.= |Colorless or |White. |Perfect in three di- |
| |white when | |rections at angles of |
| |pure, all | |about 105° or 75°. |
| |colors when | | |
| |impure. | | |
| | | | |
|=Chalcocite.= |Dark gray. |Lead-gray. |No cleavage, smooth |
| |Tarnishes | |conchoidal fracture. |
| |black or | | |
| |green. | | |
| | | | |
|=Chalcopyrite.= |Bright brass- |Greenish |No cleavage. Uneven |
| |yellow. Often |black. |fracture. |
| |tarnished iri-| | |
| |descent. | | |
| | | | |
|=Copper.= |Copper-red. |Copper-red. |No cleavage. Hackly |
| |Tarnishes | |fracture. |
| |green to | | |
| |black. | | |
| | | | |
|=Corundum.= |All colors; |White. |Often parts readily |
| |usually gray | |into almost rectangular|
| |or brown when | |pieces whose faces are |
| |massive. | |cross-hatched. |
| | | | |
|=Epidote.= |Dark green or |White. |Perfect in one direc- |
| |greenish brown| |tion. |
| |(crystals) to | | |
| |light yellow- | | |
| |ish green. | | |
| | | | |
|=Fluorite.= |All colors; |White. |Cleaves easily into |
| |green, violet,| |octahedrons, i. e., |
| |purple, color-| |in four directions, at |
| |less and | |angles of 109° or 71°. |
| |white, the | | |
| |commoner. | | |
| | | | |
|=Galenite.= |Bluish lead, |Lead-gray. |Perfect cubical, i. e.,|
| |gray. Tar- | |in three directions at |
| |nishes black. | |angle of 90°. |
| | | | |
|=Garnet.= |Commonly some |White. |No cleavage. Uneven |
| |shade of red; | |fracture. |
| |also brown, | | |
| |yellow, white,| | |
| |black, green. | | |
| | | | |
|=Gold.= |Golden yellow |Yellow to |No cleavage. Hackly |
| |to nearly |nearly white.|fracture. |
| |silver-white. | | |
| | | | |
|=Graphite.= |Dark gray to |Dark gray. |Perfect in one direc- |
| |black. | |tion. Cleavage faces |
| | | |are apt to be curved. |
| | | |Not shown if finely |
| | | |granular. |
| | | | |
|=Gypsum.= |White, gray, |White. |Very perfect in one |
| |red, yellow or| |direction; two others |
| |other tints | |show as cracks at angle|
| |due to | |of 114°, on the perfect|
| |impurities. | |cleavage faces. |
| | | | |
|=Halite.= |Colorless or |White. |Perfect cubic i. e., in|
| |white when | |three directions at |
| |pure. Yellow, | |angle of 90°. |
| |brown, red, | | |
| |etc., when | | |
| |impure. | | |
| | | | |
|=Hematite.= |Black when |Red. |No cleavage; may have a|
| |metallic; red-| |parting in one direc- |
| |dish black | |tion producing a platy |
| |when dull, red| |structure. Uneven |
| |when earthy. | |fracture. |
| | | | |
|=Limonite.= |Yellow, brown |Yellow or |No cleavage. Uneven |
| |or nearly |yellowish |fracture. |
| |black. |brown. | |
| | | | |
|=Magnetite.= |Iron-black. |Black. |No cleavage. Sometimes |
| | | |parts in four direc- |
| | | |tions at angles of 109°|
| | | |and 71°. Uneven to sub-|
| | | |conchoidal fracture. |
| | | | |
|=Malachite.= |Green, often |Green. Paler |No cleavage. Uneven |
| |nearly black |than the |fracture. |
| |on exposed |color. | |
| |surfaces. | | |
| | | | |
|=Muscovite.= |White or light|White. |Very perfect in one |
| |tints of other| |direction, yielding |
| |colors, par- | |thin sheets. |
| |ticularly | | |
| |gray, brown or| | |
| |green. | | |
| | | | |
|=Orthoclase.= |Flesh-red, |White. |In two directions at |
| |gray, yellow, | |angle of 90°, one di- |
| |white or | |rection slightly less |
| |colorless. | |perfect than the other.|
| | | | |
|=Pyrite.= |Pale to deep |Black. |No cleavage. Conchoidal|
| |brass-yellow. | |to uneven fracture. |
| |Tarnishes | | |
| |brown or | | |
| |iridescent. | | |
| | | | |
|=Pyrolusite.= |Black to dark |Sooty black. |May appear to have good|
| |steel-gray. | |cleavage in one direc- |
| | | |tion but usually shows |
| | | |none. |
| | | | |
|=Pyroxene.= |Black or light|White to |Poor in two directions |
| |to dark green.|greenish. |at angle of nearly 90°.|
| | | |May have a fine platy |
| | | |parting. |
| | | | |
|=Quartz.= (Pheno-|White or |White or |No cleavage. Single |
|crystalline). |colorless when|light tints. |crystal has conchoidal |
| |pure. All | |fracture, otherwise the|
| |colors when | |fracture is uneven. |
| |impure. | | |
| | | | |
|=Quartz.= (Cryp- |... |... |No cleavage. Conchoidal|
|tocrystalline). | | |fracture. |
| | | | |
|=Serpentine.= |Light to dark |White. No |Conchoidal fracture |
| |green, yellow,|cleavage. |when massive. |
| |brownish red, | | |
| |variegated. | | |
| | | | |
|=Siderite.= |Light to dark |White to |Very perfect in three |
| |brown or gray.|yellowish. |directions at angle of |
| |Tarnishes red-| |107° and 73°. Not |
| |dish brown or | |evident when fine |
| |brownish | |grained. |
| |black. | | |
| | | | |
|=Sphalerite.= |Commonly yel- |White, yellow|Very perfect in six |
| |low, brown, |or brown. |directions at angles of|
| |black or red; | |60°, 90° and 120°. |
| |sometimes | | |
| |green or | | |
| |white. | | |
| | | | |
|=Stibnite.= |Light gray. |Lead-gray. |Perfect in one direc- |
| |Cleavage faces| |tion, yielding blade- |
| |appear silver | |like strips which are |
| |white when | |bent or hatched perpen-|
| |reflecting | |dicular to their |
| |light. | |length. |
| | | | |
|=Talc.= |White, light |White to |Perfect in one direc- |
| |green, gray; |greenish. |tion, yielding thin |
| |other colors | |flexible plates. Not |
| |when impure. | |shown on the fine |
| | | |grained soapstone. |
| | | | |
|=Tetrahedrite.= |Gray. |Gray, brown, |No cleavage. Uneven, |
| | |or reddish. |granular fracture. |
| | | | |
|=Tourmaline.= |All colors. |White. |No cleavage. Uneven to |
| |Interior and | |poor conchoidal |
| |exterior or | |fracture. |
| |opposite ends | | |
| |of a crystal | | |
| |may differ in | | |
| |color. | | |
| | | | |
|=Zoisite.= |White, gray, |Uncolored. |Parallel cleavage; |
| |yellow, brown.| |sometimes fibrous. |
+-----------------+--------------+-------------+-----------------------+
+-----------------+-----------------------+--------------+-------------+
|=Name of Mineral=| =Crystallization and | =Tenacity |=Diaphaneity=|
| | Occurrence= | etc.= | |
+-----------------+-----------------------+--------------+-------------+
|=Amphibole.= |Prismatic crystals with|Brittle to |Opaque to |
| |hexagonal cross-sec- |tough. |transparent. |
| |tion, common; also | | |
| |cleavable masses. | | |
| | | | |
|=Arsenopyrite.= |Crystals resemble a |Brittle. |Opaque. |
| |double-edged axe. | | |
| |Occurs also coarse to | | |
| |fine granular. | | |
| | | | |
|=Barite.= |Diamond shaped or rect-|Brittle. |Transparent |
| |angular tabular, or | |to |
| |prismatic crystals and | |translucent. |
| |platy masses. | | |
| | | | |
|=Biotite.= |Six-sided tabular crys-|Flexible and |Opaque to |
| |tals, and as scales, |elastic. |transparent. |
| |plates, or scaly | | |
| |masses. | | |
| | | | |
|=Calcite.= |Prismatic or tabular |Brittle. |Transparent |
| |six-sided crystals; | |to opaque. |
| |also granular, | | |
| |cleavable, or earthy | | |
| |masses. | | |
| | | | |
|=Chalcocite.= |Usually very compact |Slightly |Opaque. |
| |masses; six-sided, |sectile. | |
| |tabular crystals rare. | | |
| | | | |
|=Chalcopyrite.= |Occurs massive or in |Brittle. |Opaque. |
| |scattered particles. | | |
| |Crystals usually have | | |
| |four triangular faces. | | |
| | | | |
|=Copper.= |Masses, plates, scales,|Malleable |Opaque. |
| |branching aggregates |sectile. | |
| |and octahedral crys- | | |
| |tals, usually | | |
| |distorted. | | |
| | | | |
|=Corundum.= |Prismatic or tabular |Brittle to |Translucent |
| |six-sided crystals; |tough. |to |
| |also granular and | |transparent. |
| |pseudo-cleavable | | |
| |masses. | | |
| | | | |
|=Epidote.= |Slender, deeply grooved|Brittle. |Transparent |
| |prismatic crystals and | |to opaque. |
| |cleavable to fine | | |
| |granular masses. | | |
| | | | |
|=Fluorite.= |In groups of crystals, |Brittle. |Transparent |
| |usually cubical; also | |to |
| |in cleavable masses. | |translucent. |
| |Sometimes granular. | | |
| | | | |
|=Galenite.= |Cubical crystals, often|Very Brittle. |Opaque. |
| |with triangular faces | | |
| |on the corners; also, | | |
| |cleavable to granular | | |
| |masses. | | |
| | | | |
|=Garnet.= |Complex, rounded crys- |Brittle. |Transparent |
| |tals, glassy masses and| |to opaque. |
| |granular. | | |
| | | | |
|=Gold.= |Nuggets, plates, |Malleable |Opaque. |
| |scales, wires; |sectile. | |
| |branching aggregates | | |
| |and distorted crystals,| | |
| |usually octahedral. | | |
| | | | |
|=Graphite.= |Imbedded scales and |Sectile |Opaque. |
| |foliated, granular or |Flexible. | |
| |compact masses. Rarely | | |
| |in six-sided, tabular | | |
| |crystals. | | |
| | | | |
|=Gypsum.= |Diamond shaped crys- |Sectile, Thin |Translucent |
| |tals, and cleavable, |flakes, |to |
| |fibrous, granular, |flexible. |transparent. |
| |foliated or compact | | |
| |masses. | | |
| | | | |
|=Halite.= |Cubical or octahedral |Brittle. |Translucent |
| |crystals; also | |to |
| |cleavable, granular or | |transparent. |
| |compact masses. | | |
| | | | |
|=Hematite.= |Complex, tabular or |Brittle. |Opaque. |
| |rounded crystals; also | | |
| |platy, oolitic, earthy,| | |
| |micaceous, and kidney | | |
| |shaped masses. | | |
| | | | |
|=Limonite.= |Botryoidal or stalac- |Brittle. |Opaque. |
| |titic forms with a | | |
| |radiating fibrous | | |
| |structure and a | | |
| |varnish-like surface, | | |
| |also earthy masses and | | |
| |concretions. | | |
| | | | |
|=Magnetite.= |Octahedral crystals, |Brittle. |Opaque. |
| |and coarse to fine | | |
| |granular, laminated, or| | |
| |compact masses. | | |
| | | | |
|=Malachite.= |Massive, as botryoidal |Brittle. |Translucent |
| |crusts with a radiating| |to opaque. |
| |structure and silky | | |
| |lustre, and as slender | | |
| |crystals forming | | |
| |velvety surfaces. | | |
| | | | |
|=Muscovite.= |Six-sided, tabular |Flexible and |Transparent |
| |crystals, and as |elastic. |to |
| |scales, plates, or | |translucent. |
| |scaly masses. | | |
| | | | |
|=Orthoclase.= |Thick-set square or |Brittle. |Transparent |
| |six-sided crystals, or | |to opaque. |
| |cleavable masses or | | |
| |grains. | | |
| | | | |
|=Pyrite.= |Cubical, octahedral, or|Brittle. |Opaque. |
| |complexly rounded crys-| | |
| |tals, coarse to fine | | |
| |granular, and massive. | | |
| | | | |
|=Pyrolusite.= |Occurs as radiating |Brittle. |Opaque. |
| |prismatic layers, | | |
| |velvety crust and | | |
| |granular to compact | | |
| |masses. Soils the | | |
| |fingers. | | |
| | | | |
|=Pyroxene.= |Prismatic crystals with|Brittle. |Transparent |
| |square or octagonal | |to opaque. |
| |cross-section; also | | |
| |foliated and massive. | | |
| | | | |
|=Quartz.= (Pheno-|Six-sided prism termi- |Brittle. |Transparent. |
|crystalline). |nated by a six-sided | | |
| |pyramid; also massive, | | |
| |coarse to fine | | |
| |granular, and as sand. | | |
| | | | |
|=Quartz.= (Cryp- |Very fine grained |Brittle. |Translucent |
|tocrystalline). |massive, botryoidal, | |to opaque. |
| |nodular, or filling or | | |
| |lining cavities in | | |
| |rocks. | | |
| | | | |
|=Serpentine.= |Compact, massive or |Tough. Fibres |Translucent |
| |coarse to fine fibrous.|are flexible. |to opaque. |
| |The two habits are | | |
| |often in parallel | | |
| |layers. | | |
| | | | |
|=Siderite.= |Cleavable masses, |Brittle. |Translucent |
| |coarse to fine, | |to opaque. |
| |granular and at warped | | |
| |crystals that resemble | | |
| |distorted cubes. | | |
| | | | |
|=Sphalerite.= |Complexly rounded or |Brittle. |Transparent |
| |modified cubical crys- | |to opaque. |
| |tals; also cleavable, | | |
| |coarse to fine granular| | |
| |masses, and botryoidal,| | |
| |etc. | | |
| | | | |
|=Stibnite.= |Sharp, vertically |Very brittle. |Opaque. |
| |grooved, prismatic | | |
| |crystals and in | | |
| |cleavable masses with a| | |
| |bladed structure. | | |
| | | | |
|=Talc.= |Foliated, coarse to |Tough sectile.|Transparent |
| |fine granular, or | |to |
| |compact masses. Feels | |translucent. |
| |greasy to soapy. | | |
| | | | |
| | | | |
|=Tetrahedrite.= |Crystals have four |Brittle. |Opaque. |
| |triangular faces. | | |
| |Occurs usually granular| | |
| |massives. | | |
| | | | |
|=Tourmaline.= |Vertically lined, |Very brittle. |Transparent |
| |prismatic crystals with| |to opaque. |
| |spherical triangular | | |
| |cross-sections. Also | | |
| |columnar or compact | | |
| |massive. | | |
| | | | |
|=Zoisite.= |Occurs in tri-metric |Brittle. |Transparent, |
| |crystals; also massive.| |translucent. |
+-----------------+-----------------------+--------------+-------------+
+-----------------+-------------------------+--------------------------+
|=Name of Mineral=| =Varieties= | =Remarks= |
+-----------------+-------------------------+--------------------------+
|=Amphibole.= |Actinolite (green, trans-|Common constituent of |
| |parent). Asbestos |igneous and metamorphic |
| |(fibrous, dull). Horn- |rocks. Valueless. |
| |blende (black). | |
| | | |
|=Arsenopyrite.= |... |Principal ore of arsenic |
| | |and sometimes carries |
| | |gold. Gives sparks and |
| | |garlic odor when struck |
| | |with a hammer. Yellow |
| | |tarnish. |
| | | |
|=Barite.= |... |Used to adulterate white |
| | |lead and give weight to |
| | |paper. Often associated |
| | |with lead ores. Very |
| | |heavy. |
| | | |
|=Biotite.= |... |Common constituent of |
| | |igneous rocks. May be |
| | |brittle when altered. |
| | |Valueless. |
| | | |
|=Calcite.= |Marble (granular). Lime- |Effervesces vigorously in |
| |stone (dull, compact). |hydrochloric acid of any |
| |Chalk (soft, white, |strength and temperature. |
| |earthy). Mexican Onyx |Used as flux, building or |
| |(compact, banded). |ornamental stone, to make |
| | |lime, etc. |
| | | |
|=Chalcocite.= |... |An important ore of |
| | |copper. Cuts easily, |
| | |yielding a highly polished|
| | |surface. |
| | | |
|=Chalcopyrite.= |... |One of the most important |
| | |ores of copper and often |
| | |carries silver and gold. |
| | |Is often mistaken for the |
| | |latter. |
| | | |
|=Copper.= |... |The value and uses of |
| | |copper are well known. |
| | |Often carries some silver.|
| | | |
|=Corundum.= |Ruby (red). Sapphire |A very valuable gem |
| |(blue, etc.). Adamantine.|mineral and a fine |
| |Spar (massive). Emery |abrasive. See plate I, |
| |(granular, impure). |figures 10, 11 and 13. |
| | | |
|=Epidote.= |... |Common constituent of |
| | |metamorphic rocks. Rarely |
| | |cut as a gem. |
| | | |
|=Fluorite.= |Rock fluorite (finely |Used as a flux in smelting|
| |granular and usually very|ores, and in several arts |
| |impure and hard). |and trades. |
| | | |
|=Galenite.= |Steel galena (very fine |Most important lead and |
| |grained masses). Often |silver ore. Often contains|
| |rich in silver. |the latter metal with |
| | |sometimes gold and other |
| | |elements. |
| | | |
|=Garnet.= |... |An important abrasive and |
| | |a beautiful gem. Found in |
| | |metamorphic rocks. See |
| | |plate I, figures 8 and 15.|
| | | |
|=Gold.= |Based upon and named |The value and uses of gold|
| |after any impurities that|are well known. |
| |may be present. | |
| | | |
|=Graphite.= |... |Used in the manufacture of|
| | |lubricants, infusible |
| | |crucibles, and “lead” |
| | |pencils. |
| | | |
|=Gypsum.= |Selenite (cleavable, |Is carved into vases, |
| |transparent). Satin spar |statues, etc., and forms |
| |(white, fibrous, silky). |plaster of paris when |
| |Alabaster, (white, fine |calcined and ground. Is a |
| |grained). |precipitate rock. |
| | | |
|=Halite.= |... |Tastes salty. Enormous |
| | |quantities are used to |
| | |season food, in various |
| | |arts and trades, and as a |
| | |source of sodium and its |
| | |salts. A precipitate rock.|
| | | |
|=Hematite.= |Specular iron (mirror- |The most important ore of |
| |like plates or crystals).|iron, and is also used to |
| |Red Ochre or Ruddle (red,|make cheap paint, |
| |earthy). |polishing powder, etc. |
| | | |
|=Limonite.= |Bog iron ore (porous, |Commonest, but most impure|
| |earthy, often encloses |ore of iron, and is also |
| |vegetation). Yellow ochre|used to make cheap yellow |
| |or umber (earthy with |and brown paint. |
| |clay, etc.). | |
| | | |
|=Magnetite.= |Lodestone (a natural |The only black, brittle, |
| |magnet). |magnetic mineral, and a |
| | |very pure and valuable |
| | |ore of iron. |
| | | |
|=Malachite.= |... |Is an ore of copper and is|
| | |used as an ornamental |
| | |stone and in jewelry. |
| | |Azur-malachite is |
| | |malachite mixed with blue |
| | |azurite. See plate I, |
| | |figure 4. |
| | | |
|=Muscovite.= |... |Used in stove doors, as |
| | |insulation in electrical |
| | |apparatus, and for |
| | |spangling or frosting |
| | |paper and fabric. |
| | | |
|=Orthoclase.= |Sanadine (transparent |Associated with quartz and|
| |crystals or grains im- |mica in many rocks. Used |
| |bedded in igneous rocks).|in making glass and |
| | |porcelain. Next to quartz |
| | |in frequency of |
| | |occurrence. |
| | | |
|=Pyrite.= |... |Used in making sulphuric |
| | |acid and often contains so|
| | |much gold, silver and |
| | |copper as to make it an |
| | |ore of these metals. |
| | | |
|=Pyrolusite.= |... |Has many uses and is |
| | |valuable. Usually |
| | |associated with a very |
| | |fine grained, hard, black |
| | |mineral that is often |
| | |botryoidal. |
| | | |
|=Pyroxene.= |Diopside (light green, |A common constituent of |
| |glassy). Diallage (light |igneous rocks. Diopside is|
| |green, dull, foliated). |sometimes used as a gem. |
| |Auagite (black). | |
| | | |
|=Quartz.= (Pheno-|Rock crystal (colorless, |The commonest of all |
|crystalline). |transparent). Amethyst |minerals. A constituent of|
| |(purple). Rose (pink). |most rock. Great quanti- |
| |False topaz or Citrine |ties are used as a flux in|
| |(yellow). Smoky quartz or|smelting, as abrasives, |
| |Topaz (brown or gray). |and in the manufacture of |
| |Milky (white). Ferrugi- |glass and porcelain. The |
| |nous (iron stained). |transparent varieties of |
| | |pleasing tints are used as|
| | |gems. Water-clear spheres |
| | |are very valuable. |
| | | |
|=Quartz.= (Cryp- |Chalcedony (drab). Car- |... |
|tocrystalline). |nelian (red, trans- | |
| |lucent). Jasper (red, | |
| |brown, yellow, opaque). | |
| |Heliotrope or Bloodstone | |
| |(dark green with red | |
| |spots). Flint (dark gray | |
| |concretions). Agate | |
| |(banded or particolored).| |
| |Onyx (agate with flat | |
| |layers). Petrified wood | |
| |(wood replaced by | |
| |quartz). | |
| | | |
|=Serpentine.= |Precious or noble |Chrysolite is the best |
| |(massive, translucent). |commercial asbestos. Other|
| |Chrysolite (silky, |varieties are used as |
| |fibres). Verde antique |ornamental stone and |
| |(massive with calcite). |occasionally in jewelry. |
| | | |
|=Siderite.= |Sphaerosidirite or Clay- |The most valuable ore of |
| |ironstone (concretions of|iron, but is rather un- |
| |fine grained siderite |common. The impure clay- |
| |mixed with clay). |ironstone is fairly common|
| | |in sediments. |
| | | |
|=Sphalerite.= |... |The commonest zinc ore and|
| | |an impure variety |
| | |furnishes most of the |
| | |cadmium of commerce. |
| | |Associated with galenite |
| | |and silver minerals. |
| | | |
|=Stibnite.= |... |The chief source of |
| | |antimony and its salts. |
| | |Sometimes carries gold and|
| | |silver. |
| | | |
|=Talc.= |Steatite or soapstone |Used in making porcelain, |
| |(granular, impure, hard- |polishing powder, lubri- |
| |ness up to 2-1/2). French|cants, gas jets, tinted |
| |chalk (white, fine |plasters, paper, soap, |
| |grained soft). |leather dressing, talcum |
| | |powder, slate pencils, and|
| | |in other ways. |
| | | |
|=Tetrahedrite.= |... |Often contains enough |
| | |silver to make it a valu- |
| | |able ore of this metal as |
| | |well as copper. |
| | | |
|=Tourmaline.= |Schorl (black). Rubellite|A popular semi-precious |
| |(pink). Indicolite |gem. When heated (not |
| |(blue). Achroite (white).|above 212° F.), will |
| | |usually pick up bits of |
| | |paper. Opposite ends of |
| | |crystals have different |
| | |forms. |
| | | |
|=Zoisite.= |... |Often a constituent of |
| | |metamorphic rocks. |
+-----------------+-------------------------+--------------------------+
=Antimony and Bismuth.= Antimony is produced in Germany, France,
Italy, Hungary, United States, Japan and other countries.
_Bismuth_ comes mainly from Bolivia and Australia. Some is produced in
Saxony and England.
_Stibnite_ (antimony sulphide) is the chief ore of antimony. Bismuth
occurs in small amounts in a pure state and also combined with sulphur.
These metals form many alloys such as type metal, anti-friction metals,
white metal, babbitt metal, fusible metals.
_Tartar emetic_ and other antimony compounds are used in medicine and
dyeing.
=Amber= is a fossil resin found chiefly along the shores of the Baltic.
It is used in making mouthpieces for pipes, cigar holders, beads and
other articles.
=Arsenic.= Germany, England, Canada, the United States and Spain produce
the ores. Chemical laboratories transform them into the useful
compounds.
_Arsenopyrite_ (arsenic and iron sulphide), orpiment and realgar
(sulphides of arsenic) and the sources of arsenic.
_Arsenic_ (white arsenic, arsenious acid or oxide of arsenic), paris
green and other compounds and salts are prepared.
Sheep dip, rat poison, insecticides, embalming fluid, pigments and dyes
are prepared with arsenic compounds. Arsenic salts are used in preparing
certain coal-tar colors.
=Asphaltum= (or mineral pitch) is a bituminous mineral substance found
more or less pure, in some localities. The pitch lake of Trinidad and
the Bermudez lake at the mouth of the Orinoco in Venezuela, are the
largest known deposits of moderately pure asphalt. Smaller deposits of
high grade occur in Utah, Cuba and the Barbadoes.
_Rock asphalt_ consists of sandstone or limestone impregnated with
asphalt. Much asphalt is produced in refining certain grades of
petroleum--such as those obtained in California and Texas.
Rock asphalts are mined in France, Switzerland, Sicily, California,
Kentucky and Oklahoma.
For paving rock asphalts are much used in Europe. Trinidad and
Venezuelan asphalts are exported in large quantities to the United
States and Europe. For paving, these lake asphalts are mixed with broken
stone, sand and petroleum residuum.
Pure varieties (gilsonite, marjak, glance pitch) are made into black
varnish, used for insulating, etc.
=Barium= is mined in the United States and Germany.
_Barytes_ or barite is a heavy, white mineral (barium sulphate). It is
used as a substitute or adulterant for white lead in paints, and in
making oxygen.
=Bismuth.= See antimony.
=Building Stones= are quarried for local use in all parts of the world.
_Granite_, _syenite_, _gneiss_, _basalt_ and other hard or durable
rocks.
Only stone of exceptional beauty is shipped to a great distance.
Scotland, Norway, Massachusetts, Maine and other localities produce
fine stones.
=Calcium= has no commercial use in the metallic state. Its compounds,
both natural and artificial, are of great economic importance.
_Limestone_ (calcium carbonate) is a very common rock used for building.
It may be of almost any color and coarse or fine in texture. It is found
and utilized in all parts of the world. In the United States,
Pennsylvania, Illinois, Ohio, Indiana, New York and Missouri are the
chief producers.
Lime is used in chemical industries and mortar.
_Marble_ is a name applied to limestones suitable for polishing or
ornamental work. _Mexican onyx_ is translucent. Fine marbles are
quarried in Italy, Egypt, France, Spain and Greece. Vermont, Georgia,
Tennessee and New York supply the greater part of the marble used in the
United States. Handsome marbles are imported from Carrara, Italy, and
other parts of Europe. Mexican onyx is also imported.
Chalk comes mainly from the south of England. We export some Portland
cement and import a little from Europe.
_Chalk_ is of peculiar soft texture; _whiting_ is prepared chalk used to
make putty and paints; _precipitated chalk_ is similar.
_Lime_ is made by burning (calcining) common limestones. _Portland_ and
_hydraulic cements_ are prepared by calcining siliceous limestones or a
mixture of limestone and clay. They are of enormous commercial
importance, being used in concrete construction work. Europe and the
United States produce large quantities. Pennsylvania is the leading
state in this industry.
Buildings (both commercial and residences) are now being extensively
constructed of cement--in the former case being re-enforced by iron
rods.
_Chloride of lime_ (or bleaching powder), _acetate of lime_, _calcium
carbide_ and many other compounds are of industrial value.
_Gypsum_ (hydrous calcium sulphate) is used in fertilizers. Plaster is
prepared by calcining (burning) gypsum. _Plaster of paris_ is its purest
form. _Alabaster_ is compact white gypsum. It is a common mineral mined
in many parts of the world. Michigan, Kansas, New York, Ohio and other
states produce it. Fertilizers and plaster use up large quantities of
this mineral. Plaster of paris is used for casts, decorative plaster
work, cement, etc.
_Fluorite_ (calcium fluoride) is a less common mineral. Mined in
England, Kentucky and Illinois. It is used in chemical manufacture and
as a flux for ores.
_Phosphate rock_ (chiefly calcium phosphate) is important in the
preparation of fertilizers, and chemicals containing phosphorus. It is
found in deposits of organic origin in South Carolina, Florida,
Tennessee, the West Indies, Canada, Spain, France, Germany and England.
The natural phosphates are treated with sulphuric acid as a first step
in the manufacture of phosphatic fertilizers. Exported in large amount
to Germany, England and other countries.
=Carborundum=, or carbide of silicon, is harder than any known substance
but the diamond. Much is manufactured at Niagara Falls, by electrically
heating a mixture of coke, sand and salt. It is used for making
polishing powder, in grinding wheels, sharpening stones, abrasive cloth,
etc.
=Cerium.= See rare metals.
=Chrome= is mined in Asia Minor, Greece, Canada, New Caledonia and
California. Its salts are prepared in chemical laboratories.
_Chromite_ (oxide of chromium and iron) is the only ore.
_Bichromate of potash_ is the most important compound. It, together with
chromic acid, is used in tanning soft leather. A small percentage added
to steel makes it very hard and suitable for burglar-proof safes, tools,
etc. Salts of chrome are used for dyes and pigments, such as chrome
yellow, chrome green, etc.
=Coal= is one of the most important of all rocks and first among fuels.
It consists chiefly of carbon, and is universally regarded as of
vegetable origin.
Several theories as to the origin of coal have been put forth from time
to time. The one now generally accepted is that the rank and luxuriant
vegetation which prevailed during the carboniferous age grew and decayed
upon land but slightly raised above the sea; that by slow subsidence
this thick layer of vegetable matter sank below the water, and became
gradually covered with sand, mud, and other mineral sediment; that then,
by some slight upheaval or gradual silting up of the sea bottom, a land
surface was once more formed, and covered with a dense mass of plants,
which in course of time decayed, sank, and became overlaid with silt and
sand as before. At length, thick masses of stratified matter would
accumulate, producing great pressure, and this, acting along with
chemical changes, would gradually mineralize the vegetable layers into
coal.
In passing from wood or peat to coal, the proportion of carbon
increases, while that of oxygen and hydrogen decreases, these substances
being given off in the form of marsh-gas and carbonic acid gas in the
process of decay.
Deposits occur in almost all parts of the world, but many are almost
entirely undeveloped; as, for example, the coal fields of China. The
largest production is in the United States, Wales, England, Germany,
Austria, Russia and Australia. Mines are worked in India, Japan, Mexico,
South America, South Africa, China and the Philippines. Pennsylvania,
Ohio, West Virginia, Alabama, Indiana, Iowa and many other states mine
coal in great amount. Pennsylvania produces nearly all of the anthracite
and a large quantity of bituminous coal.
_Bituminous coal_, coking coal, non-coking coal, cannel coal, cherry
coal, splint coal, gas coal, steam coal, etc., are all varieties of soft
coal and contain a considerable percentage of volatile matter.
Bituminous coal is the fuel which runs the factories, railways and
steamships of the world. The distillation of coal tar and the
utilization of its numerous by-products, is one of the best examples of
modern economy which turns waste material into useful products and
large profits. Much coke is made without saving the by-products.
By distillation, bituminous coal yields gas, ammonia, coal tar and coke.
Coal tar products are numbered by the thousand. Among them are naphtha,
benzine, oil of mirbane, perfumes, flavors, drugs, saccharine, aniline
and other dyes, phenol, carbolic acid, salicylic acid, naphthaline,
photographic developers, creosote, oils, tar and pitch.
_Anthracite coal_ is almost pure carbon.
=Cobalt= is a metal the ores of which are sparingly distributed. It
generally occurs as Speiss-cobalt, cobalt-glance (or cobaltite), wad,
cobalt-bloom, linnæite and skutterudite. Its minerals are found chiefly
in the Erzgebirge Mountains, Sweden, Norway, Chile, in silver ores near
Coleman township, Ontario, in Oregon (as garnierite), and in New
Caledonia. The metal itself is of a gray color with a reddish tinge,
brittle, hard, and very magnetic.
Many of its compounds are valued on account of the brilliance and
permanence of their colors. The protoxide of cobalt, is employed in the
form of smalt in the production of the blue colors in porcelain,
pottery, glass, encaustic tiles, fresco-painting, etc., and forms the
principal ingredient in Old Sevres Blue, Thenard’s Blue, etc. The
chlorid of cobalt, dissolved in much water, may be employed as a
sympathetic ink. In dilute solutions, it is of a faint pink color, which
is not observable upon paper; but when heated before the fire, it loses
water, and becomes blue, and the writing is then capable of being read.
=Copper= is, next to iron, the most important metal in use. Its greatest
production is in the United States, in Arizona, Montana, Michigan, and
Utah. Spain, Japan, Chili, Australia and Germany produce smaller
amounts. The metal is purified by smelting, and refined, often by
electrolytic methods. There are many ores.
_Chalcopyrite_ and _bornite_ (sulphides of copper and iron) are widely
distributed.
_Chalcocite_ (copper sulphide) is mined in Montana, _malachite_ and
_azurite_ (carbonates of copper) in Arizona and metallic copper in
Michigan.
_Copper matte_ is the crude metal as it comes from the smelter.
_Brass_ and _bronze_ are alloys of copper with zinc, tin, aluminum, etc.
_Copper sulphate_ (blue vitriol) is the most important chemical compound
of copper.
The value of copper has increased within recent years, due to its
enormous use in electrical work. Aside from this, copper is employed in
large amount in the various alloys into which it enters, and in coins,
utensils, printing plates, etc. Copper sulphate is extensively used in
electrical apparatus dyes, chemical work and as an antiseptic. Large
amounts of manufactured copper are exported to Europe. Smaller
quantities of ores, matte and regulus are imported from Mexico, South
America and other countries. Copper wire is extensively used by
telephone and telegraph companies.
=Diamond.= See gems.
=Gems, or Precious Stones= are those which, because of their beauty,
hardness, and rarity, are prized for use in ornamentation, especially
in jewelry. The diamond, ruby, sapphire, and emerald are the only stones
which are, strictly speaking, entitled to be called “precious” in this
sense; but the opal, on account of its beauty, is often classed with the
precious stones; as is also the pearl, which is really not a stone, but
a secretion of a shellfish.
_Alexandrite._--A variety of chrysoberyl found in the mica slate of the
Ural mountains. It is of a rich garnet color by artificial light, by
daylight of a dark moss green. It is the only stone that so changes. The
finest specimens of alexandrite are nearly as valuable as diamonds.
_Amethyst._--A variety of crystallized quartz of a purple or
bluish-violet color, of different shades. It is much used as a jeweler’s
stone. The lighter colored ones come from Brazil, the deep purple ones
from Siberia. In value they are about the same as the garnet.
_Beryl._--A very hard mineral of much beauty when transparent. It occurs
in hexagonal prisms, commonly of a green or bluish-green color, but also
yellow, pink and white. It is a silicate of aluminum and glucinum.
Beryls are very rich in colors.
_Bloodstone._--A green siliceous stone sprinkled with red jasper, whence
the name.
_Cameo._--A figure cut in stone or shell that is composed of different
colored layers. The value depends on the artistic merit of the engraved
figure.
_Carbuncle._--A beautiful gem of a deep red color (with a mixture of
scarlet), found in the East Indies. When held up to the sun it loses its
deep tinge, and becomes of the color of a burning coal.
_Carnelian._--A variety of chalcedony, of a clear, deep red, flesh-red,
or reddish-white color. It is moderately hard, capable of a good polish,
and often used for seals. It is now used but little.
_Cat’s-eye._--A variety of quartz or chalcedony exhibiting opalescent
reflections from within, like the eye of a cat. The name is given to
other gems affording like effects, especially the chrysoberyl.
_Chalcedony._--A translucent variety of quartz, having usually a whitish
color, and a luster nearly like wax.
_Dendrite._--A stone or mineral in which are branching figures,
resembling shrubs or trees, produced by a foreign mineral, usually by an
oxide of manganese, and the moss agate.
_Diamond._--A precious stone or gem excelling in brilliancy, beauty of
prismatic colors, and remarkable for extreme hardness. It is found in
many hues--green, rose, straw, yellow, etc.--but the straw-colored ones
are the most common. The diamond is a native carbon, occurring in
isometric crystals, often octahedrons, with rounded edges. It is the
hardest substance known. Diamonds are said to be of the first water when
very transparent, and of the second and third water as the transparency
decreases.
_Diopside._--A crystallized variety of pyroxene (a silicate of lime and
magnesia), of a clear, grayish-green color; also called mussite.
_Emerald._--A precious stone of a rich green color; it is the most
valuable variety of beryl. (See beryl.)
_Epidote._--A mineral, commonly of a yellowish-green color, occurring
granular, massive, columnar, and in crystals. It is a silicate of
alumina, lime, and oxide of iron, or manganese.
_Fluorite._--Calcium fluoride, a mineral of many different colors,
white, yellow, purple, red, etc., often very beautiful. When
crystallized it is commonly in cubes with perfect octahedral cleavage.
Some varieties are used for ornamental vessels. Also called fluor spar,
or simply fluor. The colored varieties are often called false ruby,
false emerald, false topaz, false sapphire, and false amethyst.
_Flint._--A massive, somewhat impure variety of quartz, in color usually
of a gray to brown or nearly black. (See quartz.)
_Garnet._--A mineral having many varieties, differing in color and in
their constituents, but with the same general chemical formula. The
commonest color is red; the luster is vitreous, or glassy; and the
hardness is greater than that of quartz, about half as hard as the
diamond. Besides the red varieties there are also white, green, yellow,
brown and black ones.
The garnet is a silicate with various bases. The transparent red
varieties are used as gems. The garnet was the carbuncle of the
ancients. Garnet is a very common mineral in gneiss and mica slate.
The finest specimens of red garnets come from Arizona and a single carat
stone is worth about two dollars. A green variety that comes from Russia
is worth about half as much as the diamond.
_Heliotrope_ or _bloodstone_.--A green siliceous stone sprinkled with
jasper, as if with blood, whence the name.
_Hyacinth._--A red variety of zircon, sometimes used as a gem. It
resembles closely a dark Spanish topaz, and is worth a little more than
the garnet.
_Indicolite._--A variety of tourmaline of an indigo-blue color.
_Iolite._--A silicate of alumina, iron, and magnesia, having a bright
blue color and a vitreous or glassy luster. It is remarkable for its
dichroism, and is also called dichroite.
_Jacinth._--Same as hyacinth.
_Jade._--A stone commonly of a pale to dark green color, but sometimes
whitish. It is hard and very tough, capable of a fine polish, and is
used for ornamental purposes and for implements, especially in eastern
countries and among many primitive peoples.
_Jasper._--An opaque, impure variety of quartz, of red, yellow, and
other dull colors, breaking with a smooth surface. (See quartz.)
_Labradorite._--A kind of feldspar, commonly showing a beautiful play of
bluish-gray colors, and, hence, much used for ornamental purposes. The
finest specimens come from Labrador.
_Lapis-lazuli_ or _lazuli_.--A mineral of a fine azure-blue color,
usually occurring in small rounded masses. It is essentially a silicate
of alumina, lime, and soda, with some sodium sulphide. It is often
marked by yellow spots or veins of sulphide of iron, and is much valued
for ornamental work.
_Moonstone._--A nearly pellucid variety of feldspar, showing pearly or
opaline reflections from within.
The best specimens come from Ceylon. Their value is not much more than
the expense of cutting.
_Obsidian._--A kind of glass produced by volcanoes. It is usually of a
black color and opaque, except in thin splinters.
_Onyx._--Chalcedony in parallel layers of different shades of color. It
is used for making cameos, the figure being cut in one layer with the
next layer as a background (see cameo). It is stained black and used to
make mourning jewelry.
_Opal._--A mineral consisting, like quartz, of silica, but inferior to
quartz in hardness and specific gravity. The precious opal shows a
peculiar play of colors of delicate tints and it is highly esteemed as a
gem. One kind, with a varied play of colors in a reddish ground, is
called harlequin opal. The fire opal (which comes from Mexico) has
colors like the red and yellow of flame. This is not the cheap variety
commonly called Mexican opal.
[Illustration: =CELEBRATED HISTORIC DIAMONDS OF THE WORLD=]
+-------------------------------------+----------+--------+----------+
| =Name and Possessor= | =Carats |=Carats | =Dis- |
| | (Cut=) |(Uncut=)| covered= |
+-------------------------------------+----------+--------+----------+
| 1. Great Mogul Indian Moguls| 280 | ... |17th Cent.|
|2-11. Pitt or Regent King of| 136-7/8 | 410 | 1702 |
| Prussia| | | |
| 3-5. Florentine Emperor of| 139-1/2 | ... | ... |
| Austria| | | |
|4-12. Star of the Brazilian| 127 | 254 | 1853 |
| South Government| | | |
| 6. Sancy Czar of| 53-1/2 | 83 |15th Cent.|
| Russia| | | |
| 7. Green Diamond Dresden Museum | 40 | ... | ... |
|8-10. Koh-i-noor Crown of England |{280 (Old)| ... | B. C. 56 |
| |{106-9/16 | | |
| | (New) | | |
| 9. Hope Mrs. E. B. McLean,| 44-1/2 | ... | ... |
| Washington, D. C.| | | |
+-------------------------------------+----------+--------+----------+
=OTHER NOTED DIAMONDS=
+-------------------------------------+----------+--------+----------+
|Cullinan I } King Edward VII|{ 561-1/2 |}3,025- | 1905 |
|Cullinan II } |{ 309-3/4 |} 3/4 | |
|Braganza King of Portugal|Never Cut | 1,680 | 1741 |
|Rajah of Mattan Rajah of Mattan| 367.9 |787-1/2 | 1756 |
| (Borneo)| | | |
|Orloff Czar of Russia (scepter)| 194-3/4 | ... | ... |
|Tavernier Stolen in 1792| ... |242-1/2 | 1668 |
|King of Portugal | 138-1/2 | 150 | 1775 |
|Light Yellow Stewart (diamond)| ... |288-5/8 | ... |
|Shah Czar of Russia| 86 | ... | ... |
|Nassac Lord (Marquis of)| 78-5/8 | 89-5/8 | ... |
| Westminster| | | |
|Porter Rhodes Found in South America| ... | 150 | 1872 |
|Blue | 67-1/2 | 112 | ... |
|Pigott Bought by Messrs. Rundell| 49 | ... | ... |
| and Bridge| | | |
|Dudley Earl of Dudley| 49-1/2 | 88-1/2 | ... |
|Star of South Africa | 46-1/2 | 83-1/2 | 1867 |
|Pasha of Egypt Khedive of Egypt| 40 | ... | ... |
|Charles the Bold | 28 | ... | ... |
+-------------------------------------+----------+--------+----------+
_Pearl._--A shelly concretion, usually rounded, having a brilliant
luster, with varying tints, formed in the mantle, or between the mantle
and shell, of certain bivalve mollusks (especially in the pearl oysters
and river mussels) and sometimes in certain univalves. Its substance is
the same as nacre or mother-of-pearl. Pearls which are round, or nearly
round, and of fine luster, are highly prized as jewels. They are sold by
carat grains instead of carats.
_Rhodonite._--Manganese spar, or silicate of manganese, a mineral
occurring crystallized and in rose-red masses. It is almost entirely
used for ornamental purposes, in slabs, blocks, etc.
_Rock crystal_ or _mountain crystal_.--Any transparent crystal of
quartz, particularly of limpid or colorless quartz. A sphere of rock
crystal of absolutely perfect clearness, about five inches in diameter,
is worth at least twenty thousand dollars.
_Rose quartz._--A variety of quartz which is pinkish red.
_Rubellite._--A variety of tourmaline varying in color from a pale
rose-red to a deep ruby, and containing lithium. It is a little more
valuable than the garnet.
_Ruby._--A precious stone of a carmine-red color, sometimes verging to
violet, or intermediate between carmine and hyacinth red. It is a
crystallized variety of corundum. The ruby from Siam is of a dark color
and is called oxblood ruby. It has about the same value as the diamond.
The ruby from Burmah, called the pigeon-blood ruby, is of a lighter
color and several times more valuable than the oxblood ruby.
_Sapphire._--A variety of native corundum or aluminium sesquioxide. As
the name of a gem the term is restricted to the transparent varieties of
blue, pink, yellow, and other colors. The best specimens of the blue
variety are nearly as valuable as the diamond. The sapphire is next to
the diamond in hardness.
_Sard._--A variety of carnelian, of a reddish-yellow or brownish color.
_Sardonyx._--A variety of onyx consisting of sard and white chalcedony
in alternate layers. (See onyx.)
_Spinel._--A mineral occurring in octahedrons of great hardness and
various colors, as red, green, blue, brown, and black, the red variety
being the gem spinel ruby. It consists essentially of aluminum
magnesium, but commonly contains iron and sometimes also chromium. The
fine specimens of spinel ruby are worth rather more than half as much as
the diamond.
_Topaz._--A mineral occurring in rhombic prisms, generally yellowish and
pellucid, also colorless, and of greenish, bluish, or brownish shades.
It sometimes occurs massive and opaque.
_Tourmaline._--A mineral occurring in three-sided prisms. Black
tourmaline is the most common variety, but there are also other
varieties, as the blue (indicolite), red (rubellite); also green, brown,
and white. The red and green varieties, when transparent, are valued as
jewels. The finest ones come from Maine, and are worth four or five
times as much as garnets.
_Turquoise._--A hydrous phosphate of alumina containing a little copper.
It has a blue, or bluish-green color, and usually occurs in
kidney-shaped masses with a nodular surface like that of a bunch of
grapes. The finest specimens are worth nearly half as much as diamonds.
_Verd antique._--A mottled-green, serpentine marble, also a green
porphyry, which is called oriental verd antique.
_Zircon._--A mineral usually of a brown or gray color. It consists of
silicon and zirconium, and is harder than the garnet. The transparent
varieties are used as gems. The red variety is called Hyacinth; a
colorless, pale yellow, or smoky-brown variety from Ceylon is called
jargon.
=Gold=, a metal valued on account of its scarcity, color, luster, and
power of resisting oxidation. It is found in nearly all parts of the
world. South Africa and the United States are the leading producers.
Australia, South America and parts of Europe possess important gold
fields.
Gold is separated from gravel (placer mines) by washing with water. The
particles of metal, being heavy, sink and can be collected. Rock
containing gold is crushed to fine powder and the gold combined with
mercury (amalgamation). Low-grade ores are treated with a solution of
cyanide of potassium which dissolves the gold and the metal is later
separated.
_Chloride of gold_, used in photographic work, is its only important
compound. Pure gold is called twenty-four carats fine. A smaller figure
indicates that the metal is alloyed to harden it.
Gold is used for money, jewelry, gold leaf (gilding) and in dentistry.
It is almost always alloyed with copper and silver. Gold is the world’s
accepted standard of value. Shipments of gold go from one country to
another chiefly to balance international business dealings. Government
treasuries and bank vaults are the chief storehouses for gold, either
as bullion or coin.
=Graphite= is almost pure carbon. It is produced in Bohemia, Ceylon,
Italy, Germany, Mexico and the United States. The deposits in Ceylon are
the largest in the world. Much of that mined in New York and Alabama is
of very high grade.
_Plumbago_ or _black lead_ is used in making crucibles, lead pencils,
lubricants for heavy machinery, stove polish, foundry facings, paint,
etc.
_Artificial graphite_ is made from coal or coke by an electric process.
Powdered graphite is mixed with fine clay in greater or less proportion
and then molded and baked to form such articles as crucibles and lead
for pencils. Graphite is imported from Ceylon to the United States, and
lead pencils from Europe.
=Iron= is the most useful of all metals. The United States, Germany,
Great Britain, Spain and France are the greatest producers of iron. Its
ores occur in almost all parts of the world. Hematite is mined in
Minnesota, Michigan, Alabama and other parts of the United States and in
Germany, England, France, Spain, Russia, etc. Limonite is also widely
distributed. Pig iron is made by smelting iron ore in a blast furnace.
The ore, mixed with limestone, is melted by burning coke, coal or
charcoal.
_Pyrite_ (iron pyrites, or fool’s gold) is found in Spain and many other
parts of the world and is valuable in the preparation of sulphuric acid
(oil of vitriol), but useless as an iron ore.
_Hematite_ (sesquioxide of iron) is the ore which supplies three-fourths
of the iron of commerce.
_Limonite_ brown (hematite) is a hydrous oxide and furnishes nearly
one-fourth of the world’s supply of the metal. Magnetite and siderite
are less common ores.
_Pig iron_ is the crude form of the refined metal and is transformed
into cast iron, wrought iron and steel in their multitudinous forms.
These three forms of iron differ in hardness, strength, elasticity,
malleability, etc., according to the amounts of carbon, sulphur,
phosphorus, manganese and other elements.
_Ochers_ and metallic paints are iron oxides. _Prussian blue_ and
_copperas_ are iron compounds.
The United States manufactures more iron and steel than any other
country. Almost half of the production is in Pennsylvania. _Cast iron_
appears in many articles but is weaker than other forms of iron.
_Wrought iron_ contains less impurity and is used for bars, plates,
wire, structural material and parts of machinery. _Steel_ (Bessemer,
Siemens-Martin, open hearth, etc.) contains more carbon than wrought
iron, possesses both strength and hardness, and is used for rails,
structural material, machinery, tools, wire rope, sheet steel, etc. Its
hardness may be increased by tempering. The United States imports iron
ore from Cuba and Spain, pig iron from Great Britain and a little
manufactured iron and steel from Europe. We export large quantities of
manufactured iron and steel.
=Lanthanum.= See rare metals.
=Lead= is the softest, heaviest, most malleable and most easily melted
of the common metals. Its ores are found in many countries but the main
supply is from the United States, Spain, Germany and Mexico. The chief
lead mines of the United States are in Missouri, Idaho, Utah, Colorado
and Kansas. Much lead bullion is from smelters where silver ores are
reduced.
_Galena_ (lead sulphide) is the only important ore; it often carries a
considerable percentage of silver. Carbonates and sulphates of lead are
less common. _Solder_ and _type metal_ are alloys of lead with tin and
antimony. _White lead_ is a carbonate, _red lead_ and _litharge_ are
oxides. _Chrome yellow_ and _orange mineral_ are lead compounds used as
pigments.
The chief use of metallic lead is in piping, sheet lead, shot and
alloys. Large amounts of ore are transformed not into metallic lead but
into white lead for use in paints. Lead ores and lead bullion are
imported from Mexico. England is the greatest importer of lead and lead
ores.
=Lithium= is the metallic base of the Alkali lithia. The metal is of a
white, silvery appearance, and is much harder than sodium or potassium,
but softer than lead. It is the lightest of all known solids, its
specific gravity being little more than half that of water. It comes
principally from South Dakota, California and Sweden.
In chemical laboratories it is converted into lithium carbonate for
medicinal tablets and mineral waters.
=Magnesium= is a metal widely distributed over the globe, and chiefly
mined in Austria, Germany and Greece. The metal is used in flash powders
for photographic use, and in chemical manufacture, in fireproofing and
lining furnaces.
_Magnesite_ (magnesium carbonate) is used in making carbon dioxide gas
and epsom salts and for preparing magnesia (calcined magnesia).
_Dolomite_ (magnesium calcium carbonate) is common limestone, used for
building. Found in many parts of the world. Calcined dolomite is used
for lining iron furnaces.
_Talc_ (hydrous magnesium silicate), soapstone or steatite, is a soft
mineral. Mined in Maryland, Virginia, North Carolina, etc., and in
Europe. It is made into laundry tubs, firebrick, hearthstones, griddles,
slate and tailor’s pencils, gas tips, etc. Imported in small amount from
France and Italy.
_Meerschaum_ or sepiolite (magnesium silicate), comes from Asia Minor
and New Mexico. It is easily carved and made into pipes and cigar
holders. Austria and France use large quantities. It is largely
imitated.
_Asbestos_ is a fibrous variety of serpentine (a magnesium silicate).
Mineral wool is an artificial fibrous mineral. It is mined in Quebec,
Canada. Another variety of asbestos comes from Italy. Mines have been
recently discovered in Wyoming. It is used as a fireproofing material.
This mineral fiber is spun and woven into fireproof fabrics for theater
curtains or made into felt building paper, pipe covering, etc.
=Mercury= (or quicksilver) is a heavy metal which is liquid at ordinary
temperatures. It is produced in Spain, the United States, Austria,
Italy and Russia. California supplies most of this country’s quota. It
is obtained by distillation of the ore.
_Cinnabar_ (sulphide of mercury) is the source of the metal, although a
little is found in nature in the pure state.
_Vermilion_ (artificially prepared cinnabar) is used in paints.
_Calomel_ and _corrosive sublimate_ are used in medicine and
_fulminates_ of mercury in explosives.
It is used principally in the extraction of gold and silver from their
ores by amalgamation. Employed in thermometers and barometers, silvering
mirrors, and in making amalgams for dental work.
=Mica= is a common mineral found in rocks in many parts of the world. It
is mined in India, Canada, North Carolina and South Dakota. Several
varieties occur (muscovite, biotite, etc.)--valuable only when found in
large sheets which can be split smoothly. Transparent sheets are used
for lamp chimneys and stove doors. It is also employed in electrical
work, and lubricating. Some is imported from India.
=Molybdenum.= See rare metals.
=Nickel= is found in the ores pyrrhotite and garnierites, mined in
largest amount in New Caledonia and Canada. Norway produces other ores.
_Garnierite_ (a silicate of nickel and magnesium) is the common ore.
Magnetic iron pyrite (_pyrrhotite_) often carries several per cent of
nickel. Sulphides and other compounds occur. _German silver_ contains
nickel, copper and zinc. It enters into other alloys.
France and Germany refine nickel from imported ore, chiefly from New
Caledonia. Nickel steel, being especially hard and tough is used for
armor plate, special machinery and wire rope. Nickel is extensively used
for cheap electro plating.
Nickel and nickel oxide are exported to Holland and England from the
United States and ores and matte are imported from Canada.
=Petroleum= (or coal oil) is obtained from wells in the United States,
Russia, Dutch East Indies, Galicia, Roumania and other countries. More
than half of the world’s output is from the United States, the leading
districts being (1) Kansas and Oklahoma, (2) California, (3) Illinois,
(4) Pennsylvania and (5) Texas. Crude oil is transported from the wells
for hundreds of miles through pipe lines to the refineries.
In its crude state, petroleum is a dark colored liquid. It yields by
distillation, first: light oils, _gasoline_, _naphtha_, _benzine_;
second: _illuminating oils_, _kerosene_, _headlight oil_, etc.; third:
_lubricating oils_, _engine oil_, _cylinder oil_, _machine oil_; fourth:
_petroleum residuum_ (for asphalt paving) and _coke_. _Petrolatum_,
_vaseline_ and _paraffin wax_ are by-products in petroleum refining.
American kerosene oil is exported to all parts of the globe. Crude oil
is also exported as well as other petroleum products.
=Platinum= is a rare metal found with gold, iridium and other rare
metals in placer mines. It comes chiefly from Russia. Smaller amounts
from Colombia, California, Canada and Australia.
It is used in the terminals of incandescent electric lamps, and also
employed by chemists, jewelers and dentists.
=Potash= (or potassium) is an alkaline metal. Chlorides, sulphates,
etc., are found in Germany. Wood ashes and sugar beet refuse furnish
much of the world’s potash. Stassfurt, Germany, possesses the only known
large deposit of natural potash salts. These salts are the source of
potash in many chemical industries and in fertilizers. It is exported in
large amount from Germany to England, France and America.
=Quartz= (silica) is of many varieties, crystalline to amorphous.
_Rock flint_ is mined in Connecticut and Pennsylvania, and also comes
from the chalk cliffs of England and France.
_Sandstones_ are quarried and used for building in almost all parts of
the world. Pennsylvania, Ohio, and New York supply the greatest
quantities in the United States. _Honestones_ and _whetstones_ are
mostly sandstone, and in this country are largely quarried in Arkansas,
Michigan and New Hampshire.
_Rock crystal_ is employed for lenses. Many semiprecious stones are
varieties of quartz, as _agate_, _moss agate_, _onyx_, _sard_,
_chalcedony_, _chrysoprase_, _jasper_, etc.
_Rock flint_ and _quartz sand_ are used in making glass and pottery.
Outside of building stones, quartz is used in greatest amount in making
glass and pottery. For glass it is melted with alkali (soda ash) and
either lime or lead oxide. Glass is either blown or molded. Belgium,
Austria, Germany, France, Great Britain and the United States
manufacture glassware. Pennsylvania, Indiana and New Jersey are the
leading states.
=Radium= is the most characteristic of those substances which possess
the property of radio-activity--i.e. have the power of producing
photographic or electric effects by a process identical with or
analogous to radiation. The property was first observed in _uranium_ by
Becquerel in 1896--hence the name “Becquerel rays.” In 1898 Schmidt and
Madame Curie discovered almost simultaneously that the compounds of
_thorium_ had the same radio-active property; and further elaborate
investigations led to the discovery of _polonium_, _radium_, and
_actinium_, as new substances with radio-active properties. Polonium was
the name given by M. and Mme. Curie to the radio-active component of
bismuth separated from pitchblende. Its activity is transient. In the
new field of research thus opened up important work has been done by
Rutherford, Crooks, Ramsay, Soddy, Huggins, and others.
Radium is derived from _pitchblende_, in which it exists in very small
quantities. After a long-continued process of fractional crystallization
it has been prepared in the form of a tolerably pure salt. The process
of obtaining the element is very tedious. One to two kilograms of impure
radium bromide can be procured from a ton of pitchblende residue only
after processes extending over months. For the remarkable chemical
properties of radium, see further under Radio-activity.
=Rare Metals.= These include chiefly the following: _Tungsten_,
_molybdenum_, _vanadium_ and _uranium_. They are found in Colorado,
Arizona, Germany, England and Sweden. The ores of these metals are
unusual minerals, and the metals themselves are used in making special
high grades of steel. Their salts are used in dyeing.
_Thorium_, _cerium_, _lanthanum_ and _yttrium_, found in North Carolina,
Norway, Brazil and Ceylon, are also to be classified under this head.
Monazite, samarskite, thorite and other rare minerals contain these
elements. They are used in preparing the mantles for incandescent gas
lights.
=Silver=, the more common precious metal, is produced in greatest amount
in the Rocky Mountains and the Andes. The United States, Mexico,
Australia, Bolivia, Chili, Peru and Germany contribute nearly the entire
supply. Montana, Colorado, Nevada and Utah lead in silver production in
the United States. The ores are usually smelted and refined to purify
the metal.
_Argentiferous galena_ (lead ore) is the commonest ore of silver. The
amount of silver per ton varies greatly. Zinc and copper ores often
carry silver. Many sulphides of silver (argentite, pyrargyrite, etc.)
are found, as well as chlorides and bromides (cerargyrite and
bromyrite). _Chloride_ and _nitrate of silver_ are used in photography.
Silver is manufactured into innumerable articles for household use and
personal adornment. The cheapest articles are not solid (sterling) but
are electrically plated with a very thin coating of silver. Silver coins
form the bulk of the currency of the world, although in most countries
gold is the standard.
=Sodium= is the most important alkaline metal, and has a wide use.
_Salt_ (rock salt, sea salt, lake salt, halite or sodium chloride) is
the commonest natural compound of sodium. Important for food and in
chemical manufacture.
Rock salt is mined in Germany, Austria, Spain, England, Louisiana,
Kansas, India and other parts of the world. Obtained by evaporating salt
water from wells in England, Michigan, New York, Ohio and China, or by
evaporating salt water in the West Indies, Great Salt Lake, etc.
Besides its use for meat packing, curing fish, domestic purposes, etc.,
it is employed in silver refining, and the preparation of hydrochloric
acid, soda ash, carbonate of soda and other chemical products.
_Soda niter_ (nitrate of sodium) is a very easily soluble mineral. It is
found in quantity only in the deserts of northern Chili, and is exported
in large amounts to Europe and America for fertilizer and the
manufacture of nitric acid and other chemicals.
_Borax_ (hydrous sodium borate) occurs in nature in an impure form and
is prepared also from calcium borates. Borates are found in Tuscany,
Central Asia, California and Nevada, and in South America.
Borax and boracic acid are used in pottery manufacture, for the
preservation of meat, in dyeing and in medicine.
=Strontium= is found in Germany, Scotland, Texas and New York.
Strontianite (strontium carbonate) and celestite (strontium sulphate)
contain this element. Strontium salts are used in sugar refining and
making red fire.
=Sulphur= or brimstone is found in a pure state in volcanic regions or
associated with gypsum and limestone. Pyrite (sulphide of iron) is also
a source of sulphur compounds.
Sicily, Italy, Japan, Louisiana and Utah have mines of native sulphur,
which is used in manufacturing sulphuric acid, gunpowder, matches, as a
disinfectant, for bleaching and vulcanizing rubber.
Blue vitriol, green vitriol and alum are sulphates. Sulphur is imported
from Sicily and Italy.
=Thorium.= See rare metals.
=Tin= is less abundant than most of the common metals. The Malay
peninsula and nearby islands (Banca and Billiton) produce over half the
tin ore of the world. The remainder is mined in Bolivia, Australia,
Tasmania and Cornwall, England. Small deposits occur in the United
States.
Tin melts at a low temperature and is easily refined.
_Cassiterite_ (tin oxide) is the only important ore. This mineral is
commonly found as pebbles (stream tin) in gravel.
_Tinplate_ and alloys containing tin are of enormous importance in the
arts. Of these, _bronze_ is chief. _Gun metal_, _pewter_, _solder_,
_type metal_ and _britannia metal_ are other alloys. Salts of tin are
used in dyeing, glass making, etc.
Tinplate, used for tin cans, roofing and kitchen utensils, is made by
dipping sheet iron or steel in a bath of melted tin, thus covering it
with a thin layer of tin. Tinplate is manufactured in the United States
and imported from England. Tin metal is imported from England and
Straits Settlements.
=Tungsten.= See rare metals.
=Uranium.= See rare metals.
=Vanadium.= See rare metals.
=Zinc= is one of the most useful metals. Germany, United States and
Belgium supply most of the zinc. In this country, Missouri and Kansas
lead in zinc production.
_Sphalerite_ or blend (zinc sulphide) is the chief ore. Carbonates,
silicates and oxides of zinc are found. Crude zinc (_spelter_) is
distilled from roasted ore.
_Brass_, _German silver_ and other alloys contain zinc. _Galvanized
iron_ consists of a coating of zinc on sheet iron. _Zinc oxide_ (zinc
white) resembles white lead and is used in paints.
Used in electric batteries, making hydrogen, zinc etchings, etc. The
greatest amount of zinc is used in alloys and zinc compounds. Zinc and
zinc ores are both imported and exported by the United States, the
imports exceeding the exports. Zinc oxide is exported in larger amount
than any other form.
[Illustration: =HOW AND WHERE WE GET THE SALT FOR OUR FOOD=
=THE PRODUCTIVE CALIFORNIA SALT BEDS=
The United States produces one-fourth of the entire output of the world.
Salt was one of the first two great articles of international commerce
in the history of the world trade.]
[Illustration: =AN UNDERGROUND PASSAGE WAY THROUGH SOLID SALT=
The most wonderful salt mines in the world are those of Galicia, in
Austria. In this region there is a mass of salt estimated to measure 500
miles in length, 20 miles in breadth, and 1,200 feet in thickness.]