FORMS, COMPOSITIONS, CHARACTERISTICS,
ZODIACAL CLASSIFICATION, AND
PLACES OF ORIGIN
AMBER
_Hardness_: 2-2.5.
_Lustre_: Resinous.
_Chemical Composition_: Carbon 78.96. Hydrogen 10.51. Oxygen 10.52.
_Specific Gravity_: 1.10-1.13.
_Properties_: Becomes highly electric by friction. When submitted to
heat, organic compounds escape and leave a black residue.
_In the Zodiac_: Amber is under the heavenly Taurus.
_Where found_: Chiefly on the Baltic coast. On the Danish coast. Parts
of Asia, etc.
BERYL
EMERALD—AQUAMARINE
_Crystalline System_: Hexagonal.
_Hardness_: 7.5-8.
_Lustre_: Vitreous or Resinous. Transparent to translucent.
_Refraction_: Weakly double.
_Chemical Composition_: Silicate of Aluminium and Beryllium.
_Chemical Symbol_: Be_{3 Al_{2 (SiO_{3})C.
_Specific Gravity_: 2.63-2.75.
_Dichroism_: Distinct.
_Properties_: Exhibits frictional electricity. The emerald clouds
before the blowpipe flame without fusing but under intensified heat
the edges curve. With Borax the stone melts into a pale green bead.
It resists acids but is affected by microcosmic salt. The stone is so
fragile when taken out of the mine that friction crumbles it.
_In the Zodiac_: All varieties of Beryls are under the Heavenly Taurus.
_Where found_: Generally all over the world. Chiefly in Ekaterinburg,
Brazil, India, United States, Australia.
CHRYSOBERYL
ALEXANDRITE—ORIENTAL CHRYSOLITE—CYMOPHANE OR CHRYSOBERYL—CATSEYE
_Crystalline System_: Orthorhombic.
_Hardness_: 8.5.
_Lustre_: Vitreous. Transparent to translucent.
_Refraction_: Double.
_Chemical Composition_: Alumina 80.2. Glucina 19.8.
_Chemical Symbol_: BeAl_{2}O_{4}.
_Specific Gravity_: 3.7-3.86.
_Dichroism_: Strong in Alexandrite. Distinct in Chrysoberyl.
_Properties_: Crystals exhibit remarkable twinning at times.
Chrysoberyl is highly electric and when submitted to frictional
agitation holds electricity for a long time. Not affected by acids.
Under the blowpipe it is unaltered and infusible, but it fuses
tardily with borax or microcosmic salt. The Alexandrite variety
which, as Professor J. G. Dana says, bears the same relation to
ordinary Chrysoberyl as Emerald to Beryl, displays curious changes of
colour from leafy green to raspberry red in real and artificial
lights.
_In the Zodiac_: Chrysoberyl is under the Heavenly Pisces; Alexandrite
is under the Heavenly Aquarius.
_Where found_: Ceylon, Brazil, Russia, Ireland, Australia, etc.
CORUNDUM
SAPPHIRE, RUBY, ORIENTAL AMETHYST, ORIENTAL EMERALD, ETC.
_Crystalline System_: Rhombohedral.
_Hardness_: 9.
_Lustre_: Transparent to translucent.
_Refraction_: Moderately double.
_Chemical Composition_: Aluminium 53-53.2. Oxygen 46.8.
_Chemical Symbol_: Al_{2}O_{3}.
_Specific Gravity_: 3.90-4.16.
_Dichroism_: Strong.
_Properties_: Submitted to friction exhibits electrical properties
which withdraw very slowly. Acids do not affect Corundum, but under
the blowpipe in borax or microcosmic salt it gradually melts to a
transparent globule. Radium influences the colour strongly, so much
indeed as to impart it in achromatic specimens. The stone is
variously affected by heat. Treated by Sir William Crooks by exposure
to high tension electric currents in a similar way to the diamond the
ruby phosphoresced with an intense red light, and the sapphire with
an intense blue. Dr. T. Coke Squance of Sunderland, well-known in
connection with radio-therapeutical research, has succeeded in
transforming a faint pink sapphire into a fine ruby. During the
process of transformation the lustre of the stone was so intensified
that it nearly assumed the brilliancy of a diamond. Dr. Squance
observed that both radium and X-rays cause a diamond to glow with a
green light. “Besides the diamond,” he says, "a mineral called
Kunzite glows with a lovely red hue. I submitted a sapphire to the
Radium rays for a long period and it turned to a glorious red. In
fact, it had become a ruby. I have similarly transformed other
stones, a faint green sapphire, for instance, turning into an
oriental emerald." Sir William Crooks noted the sage-green colour of
the diamond under Radium, but found that the colour could easily be
removed by mechanical means.
_In the Zodiac_: Blue and green sapphires are under the Heavenly
Aquarius; white are under the Heavenly Pisces; yellow or Oriental
Topaz and Rubies are under the Heavenly Leo. Oriental Amethyst is
under the Heavenly Sagittarius.
_Where found_: Ceylon, China, Burma, Russia, East Indies, United States
of America, Australia (chiefly Queensland), etc.
DIAMOND
DIAMOND—BOART
_Crystalline System_: Isometric.
_Forms_: Octahedron, dodecahedron. Crystals frequently twinned.
_Hardness_: 10. Scratches every other stone.
_Lustre_: Adamantine. Transparent and when dark, translucent.
_Refraction_: Single.
_Chemical Composition_: Pure Carbon.
_Chemical Symbol_: C.
_Specific Gravity_: 3.50-3.55.
_Properties_: Exhibits positive electricity when rubbed, but is itself
a non-conductor of electricity. When intensely heated it burns,
yielding Carbonic Anhydride. When heated so as to exclude chemical
combination it dilates and forms into a black concretion. It displays
phosphorescence under Radium, when submitted to strong sunlight and,
when put in a vacuum tube, to a high tension electric current. Dr. G.
F. Herbert Smith found that "some diamonds fluoresce in sunlight,
turning milky, and a few emit light when rubbed." Dr. Kunz proved
that diamonds phosphoresce when exposed to the rays of Radium,
Polonium, or Actinium, even when glass is interposed. These phenomena
formed special object of experiment with the late Sir William Crooks,
who showed that exposed to high tension electric currents in greatly
rarified atmosphere, the diamond phosphoresced with an intense green
light. Prismatic colours are radiated by this gem.
_In the Zodiac_: The Diamond is under the Heavenly Aries, Leo and
Libra.
_Where found_: India, Borneo, Brazil, South Africa, Siberia, Australia,
United States of America.
GARNET
ALMANDINE, PYROPE, HESSONITE, (GARNET HYACINTH), UVAROVITE
_Crystalline Form_: Isometric.
_Hardness_: 6.5-7.5.
_Lustre_: Vitreous.
_Refraction_: Single.
_Chemical Composition_: Silica Alumina, Red Iron Oxide, Lime Magnesia,
Manganese, Protoxide.
_Chemical Symbol_: Dr. Smith has the following formulae:
Hessonite Ca_{3} Al_{2}(SiO_{4})_{3}.
Pyrope Mg_{3} Al_{2}(SiO_{4})_{3}.
Almandine Fe_{3}Al_{2}(SiO_{4}O)_{3}.
Andradite Ca_{3}Fe_{2}(SiO_{4}O)_{3}.
_Specific Gravity_: 3.4-4.3.
_Properties_: Exhibits positive electricity by friction. With the
exception of Uvarovite, all varieties of Garnets fuse before the
blowpipe flame. The stone generally does not contain water.
_In the Zodiac_: The Almandine is under the Heavenly Sagittarius; the
Pyrope, Aquarius; Hessonite, Virgo; Uvarovite, Aquarius.
_Where found_: Generally all over the world.
OPAL
_Crystalline System_: None.
_Form_: Amorphous.
_Hardness_: 5.5-6.5.
_Lustre_: Waxy to subvitreous.
_Refraction_: Single.
_Chemical Composition_: Silica 91.32. Water 8.68.
_Chemical Symbol_: SiO_{2}, n=SiO_{2}nH_{2}O.
_Specific Gravity_: 1.9-2.3.
_Properties_: No electrical properties. Opal exhibits characteristic
colour reflections known as Opalescence. It is susceptible to heat
and weather changes, exhibiting greater brilliancy on hot than on
cold days. The opal has never yet been successfully imitated, and
certain peculiar properties yet remain to be investigated. Professor
Frank Rutley F. G. S., emphasises the fact that "the nature of the
Silica (Hydrous Silica) is not yet definitely determined." It is
infusible before the blowpipe, but turns opaque.
_In the Zodiac_: The Opal is under the Heavenly Leo, Libra and
Aquarius. Leo favours red and fire opal; Libra, light translucent,
pure colours, etc.; Aquarius, dark, black Opal, etc.
_Where found_: Hungary, Honduras, Mexico, United States. The finest
opal is now found in Australia, principally at Lightning Ridge, White
Cliffs, Stuart’s Range, Charleville, etc. (Mr. Conrad H. Sayce gives
(“Australasian,” March issue, 1920) an analysis of Stuart’s Range
opal, bearing earth which contains about 35 per cent each of Alumina
and Sulphur trioxide. He opines that this may account for the harmful
effect it has on the men’s eyes and lungs.)
PEARL
_Hardness_: 3.5-4.
_Lustre_: Translucent.
_Chemical Composition_: Carbonate of Lime and Organic matter.
_Specific Gravity_: 2.65-2.89.
_Properties_: Affected by acids. Benefitted by some skins, adversely
affected by others. Destroyed by fire.
_Where found_: Persian Gulf, Ceylon, Red Sea, South America, New
Guinea, Thursday Island, Australia, etc.
_In the Zodiac_: Pearls are under the Heavenly Cancer.
PERIDOT
CHRYSOLITE—OLIVINE
_Crystalline System_: Orthorhombic.
_Hardness_: 6-7.
_Lustre_: Vitreous. Transparent to translucent.
_Refraction_: Double.
_Chemical Composition_: Silicate of Magnesium and Iron.
_Chemical Symbol_: (Mg,Fe)_{2}SiO_{4}.
_Specific Gravity_: 3.3-3.5.
_Dichroism_: Distinct.
_Properties_: Friction induces electricity in the stone which is
infusible before the blowpipe, but is affected, whitening and forming
with Borax, a yellow bead. Decomposes in Hydrochloric acid.
_In the Zodiac_: The Peridot is under the Heavenly Pisces.
_Where found_: United States, Ireland, Australia, (Queensland
particularly), etc. A large number of Meteorites contain Peridots.
QUARTZ
ROCK CRYSTAL, AMETHYST, CAIRNGORM, CHRYSOPRASE, CATSEYE, PLASMA, JASPER,
CARNELIAN, AGATE, ONYX, SARDONYX, MOSS AGATE
_Crystalline System_: Rhombohedral.
_Hardness_: 7.
_Lustre_: Vitreous. Splendent to dull and resinous.
_Refraction_: Double.
_Chemical Composition_: Silicon 46.67. Oxygen 53.33.
_Chemical Symbol_: SiO_{2}.
_Specific Gravity_: 2.5-2.8. In pure crystals 2.65.
_Dichroism_: Distinct.
_Properties_: Generates positive electricity by friction. It is
infusible under the blowpipe, but effervesces with Carbonate of Soda.
Although it resists the common acids it may be dissolved in
Hydrofluoric.
_In the Zodiac_: Rock Crystal is under the Heavenly Pisces; Amethyst is
under the Heavenly Aries; Cairngorm under the Heavenly Scorpio;
Chrysoprase under the Heavenly Cancer; Catseye under the Heavenly
Capricorn; Plasma under the Heavenly Virgo; Jasper under the Heavenly
Virgo; Bloodstone under the Heavenly Leo; Camelian under the Heavenly
Leo; Agate under the Heavenly Scorpio; Onyx under the Heavenly
Capricorn; Sardonyx under the Heavenly Leo; Moss Agate under the
Heavenly Taurus.
_Where found_: Distributed plentifully about the world. Rock Amethyst
is found in the United States, Brazil, India, Ceylon, Ekaterinburg,
Australia, etc. Mr. R. J. Dunn, late Victorian Geologist, discovered
large quantities of Rose Quartz in South Africa. It is also found in
the United States, Russia, Australia and other places. Catseyes are
found in Ceylon and India. Cairngorm is found in Scotland, United
States, Australia, etc. Chrysoprase is found in the United States and
other places.
SPINEL
SPINEL RUBY, BALAS RUBY, RUBICELLE, PLEONASTE OR CEYLONITE
_Crystalline System_: Isometric.
_Hardness_: 8-8½.
_Lustre_: Vitreous.
_Refraction_: Single.
_Chemical Composition_: Alumina 72. Magnesia 28.
_Chemical Symbol_: MgAl_{2}O_{4}.
_Specific Gravity_: 3.5-4.0.
_Dichroism_: None.
_Properties_: Does not display electricity when submitted to friction
or heat, but under heat the red spinel changes to brown. On cooling
it becomes green, after which it is nearly colourless; then it
resumes its pristine hue. Spinel crystals also change into
Hydrotalcite, a soft pearl-like stone of similar chemical
composition. Infusible alone under the blowpipe but yields slowly
with Borax. It is soluble in concentrated Sulphuric Acid.
_In the Zodiac_: Spinel, Balas, Almandine, Ruby and Sapphirine are
under the Heavenly Virgo. The Chloro-Spinel and the Pleonaste are
under the Heavenly Capricorn.
_Where found_: United States, Canada, Burma, Siam, Ceylon, Australia,
etc. It is discovered in granular limestone, in gneiss and rocks of
volcanic origin.
SPODUMENE
KUNZITE—HIDDENITE
_Crystalline Form_: Monoclinic.
_Hardness_: 6.5-7.
_Lustre_: Pearly. Translucent to subtranslucent.
_Refraction_: Double.
_Chemical Composition_: Silicate of Aluminium and Lithium.
_Chemical Symbol_: Li A1 (Si O_{3})_{2}.
_Specific Gravity_: 3.5-3.20.
_Dichroism_: Strong.
_Properties_: Electrical. Unaffected by acids. Under the blowpipe flame
expands and melts into a clear or opaque glass, indicating lithia by
colouring the flame red. Kunzite exhibits phosphorescence under
Radium.
_In the Zodiac_: Spodumene and Kunzite are under the Heavenly Libra.
Hiddenite may be under the zodiacal Taurus.
_Where found_: United States of America, Madagascar, Brazil, Sweden,
etc.
TOPAZ
_Crystalline Form_: Orthorhombic.
_Hardness_: 8.
_Lustre_: Vitreous. Transparent to translucent.
_Refraction_: Slightly double.
_Chemical Composition_: Silicate of Aluminium.
_Chemical Symbol_: [A1(F,OH)]_{2}SiO_{4}. (Penfold and Minor.)
_Specific Gravity_: 3.4-3.65.
_Dichroism_: Distinct.
_Properties_: Becomes strongly electric by friction, heat and pressure.
Infusible alone before the blowpipe flame, but with Borax melts into
a bead. Changes colour when heated.
_In the Zodiac_: The Topaz is under the Heavenly Scorpio.
_Where found_: Brazil, Ceylon, Mexico, United States, Australia, etc.
TOURMALINE
_Crystalline Form_: Rhombohedral.
_Hardness_: 7-7.5.
_Lustre_: Vitreous.
_Refraction_: Double.
_Chemical Composition_: Varied, but all varieties include silicate of
alumina, boracic acid, iron, magnesia, lime and soda, sometimes
lithia in small quantity, with fluorine and trace of phosphoric acid.
_Chemical Symbol_: Professors Penford and Foote refer all
varieties of Tourmaline to
(H_{6}Na_{6}Mg_{3}Al_{2})_{3}(Al,Fe)_{6}(B,OH)_{4}Si_{8}O_{38},
_Specific Gravity_: 2.39-3.3.
_Dichroism_: Strong.
_Properties_: Becomes charged by heat and friction with positive and
negative electricity. Before the blowpipe flame the darker varieties
fuse easily but the lighter more tardily.
_In the Zodiac_: The Tourmaline family is under the Heavenly Gemini.
_Where found_: Brazil, Russia, California and other parts of the United
States, Ceylon, Australia, etc.
TURQUOISE
_Crystalline Form_: None.
_Hardness_: 6.
_Lustre_: Waxy.
_Chemical Composition_: Dr. Smith gives the composition as a complex
phosphate of Aluminium, iron and copper.
_Chemical Symbol_: Dr. Smith gives Penfold’s formula as
[Al(OH)_{2}Fe(OH)_{2},Cu(OH),H]_{3}PO_{4},
approaching nearly to H_{5}Al_{2}PO_{8}.
_Specific Gravity_: 2.6-2.8.
_Properties_: Infusible before the blowpipe flame, but changes its
colour to brown. Dissolves in Hydrochloric acid. Is affected by
acids, oils, the health of the wearer, etc.
_In the Zodiac_: Turquoise is under the zodiacal Sagittarius.
_Where found_: Chiefly in Persia where the best specimens are found.
Also found in Mexico, Russia, United States, Australia, etc.
ZIRCON
ZIRCON, JARGOON, HYACINTH OR JACINTH
_Crystalline System_: Tetragonal.
_Hardness_: 7.5.
_Lustre_: Adamantine. Transparent to opaque.
_Refraction_: Strongly double.
_Chemical Composition_: Silica 33. Zirconia 67.
_Chemical Symbol_: ZR SiO_{4}.
_Specific Gravity_: 4.6-4.86.
_Properties_: Exhibits frictional electricity. The Zircon is infusible
before the blowpipe flame but coloured specimens lose their colours.
With borax Zircon melts under the blowpipe into a transparent bead.
Heated with lime the Zircon is transformed into a straw-coloured
stone which so closely resembles the yellow diamond that it is sold
to travellers by some unscrupulous Eastern dealers as the more costly
gem. Scientists have not yet been able to explain the constitution
and distinct characters of the Zircon satisfactorily. Professor Sir
A. H. Church has made a technical study of the zircon for over half a
century, and is universally accepted as its most authoritative
student. In his researches he found that in certain varieties of
zircon the green and yellow stones, ground on copper wheel with
diamond dust, exhibit a sparkling orange light, and the intermediate
golden types radiate orange tints in the flame of a Bunsen burner.
Students are seeking for the unknown element which, blended with
zirconium, defies detection. The Zircon is very little affected by
acids, except sulphuric acid after very long steeping. It is also
peculiar that when first heated the stone exhibits strong
phosphorescence, but as its colour leaves it, its specific gravity is
magnified and it will not again phosphoresce when reheated after
cooling.
_In the Zodiac_: All varieties of Zircon are under Heavenly Virgo.
_Where found_: In almost every part of the world.