COMPARATIVE TABLE of celebrated MINES in EUROPE and AMERICA. By F. Burr,
Esq. (_Quarterly Mining Review for July_, 1835, p. 60.)
+--------+--------------+--------------+--------------+--------------+
| |CONSOLIDATED |VETA GRANDE |MINE OF |MINE OF |
| |AND UNITED |MINES. |VALENCIANA. |HIMMELSFÜRST. |
| |MINES. | | | |
| +--------------+--------------+--------------+--------------+
| |(At present |(At present |(Richest of |(Richest of |
| |the richest |the richest |the Mexican |the Saxon |
| |mines in Corn-|mines in |mines at the |mines at the |
| |wall.) |Mexico.) |beginning of |beginning of |
| | | |the present |the present |
| | | |century.) |century.) |
| | | | | |
|Situa- |Two miles east|Four miles |One mile north|Two miles |
|tion |of Redruth. |north of |of Guanaxuato.|south-east of |
| | |Zacatecas. | |Freyberg. |
| | | | | |
|Eleva- |Elevation of |Elevation of |Elevation of |Elevation of |
|tion |the surface a-|the surface a-|the surface a-|the surface a-|
| |bove the level|bove the level|bove the level|bove the level|
| |of the sea, |of the sea, |of the sea, |of the sea, |
| |from 200 to |supposed to be|7,617 feet. |1,346 feet. |
| |300 ft.; depth|about 6000 |Elevation of |Elevation of |
| |of the bottom |feet. Eleva- |the bottom of |the bottom of |
| |of the mine |tion of the |the mine above|the mine above|
| |below the |bottom of the |the level of |the level of |
| |level of the |mine above the|the sea, 5,730|the sea, 263 |
| |sea, about |level of the |feet. |feet. |
| |1,370 feet. |sea, probably | | |
| | |near 5,000 | | |
| | |feet. | | |
| | | | | |
|Nature |The _Veta_ |The rock pre- |Primary clay |Transition |
|of the |_Madre_ of |vailing in the|slate resting |clay slate, |
|rock |Guanaxuato, |neighbourhood |immediately on|alternating |
| |upon which |of Freyberg, |granite, a |with dolomite,|
| |this mine is |in which this |short distance|and occasion- |
| |worked, tra- |and most of |westward of |ally with |
| |verses both |the other |the mines. The|greywacke. |
| |clay slate and|mines are |clay slate is |This clay |
| |porphyry, but |situate, is a |intersected by|slate is some-|
| |it is most |formation of |numerous chan-|times decom- |
| |productive in |primary |nels of por- |posed; it |
| |the former |gneiss. |phyry, which |rests on sye- |
| |rock. The clay| |have nearly |nitic rocks, |
| |slate is con- | |the same di- |and is in some|
| |sidered by | |rection as the|places covered|
| |Humboldt to | |mineral veins,|with porphyry.|
| |belong to the | |and are often | |
| |transition | |of consider- | |
| |class, but | |able width. | |
| |situate near | |The porphyry | |
| |the limits of | |sometimes | |
| |primary forma-| |appears also | |
| |tions. This | |to form large | |
| |rock in depth,| |irregular mas-| |
| |passes into | |ses in the | |
| |chlorite | |clay slate. | |
| |slate, and | |Both rocks are| |
| |talc slate. It| |traversed by | |
| |contains sub- | |veins of | |
| |ordinate beds | |quartz and | |
| |of syenite, | |clay inter- | |
| |hornblende | |secting the | |
| |slate, and | |metalliferous | |
| |serpentine. | |veins. | |
| |The porphyry | | | |
| |rests upon the| | | |
| |clay slate, | | | |
| |and is con- | | | |
| |formable to | | | |
| |it, both in | | | |
| |direction and | | | |
| |stratifica- | | | |
| |tion. | | | |
| | | | | |
|Nature |In the con- |One principal |One Veta (the |There are five|
|of the |solidated |vein (the |_Veta Madre_) |veins worked |
|metalli-|mines, the |_Veta Grande_)|which is often|in this mine. |
|ferous |eight follow- |which is gen- |separated into|The principal |
|deposits|ing lodes are |erally sepa- |three |vein (_Teich- |
| |extensively |rated into |branches, ex- |flache_) is |
| |worked:--Wheal|three |tending from |from one foot |
| |Fortune lode, |branches, and |130 to 160 |six inches, to|
| |Cusvea lode, |sometimes into|feet in width.|three feet in |
| |Deeble’s lode,|four. When |When not rami-|width, the |
| |Old lode, |ramified, the |fied, its |others are |
| |Taylor’s lode,|width extends |width varies |from six to 12|
| |Tregonning’s |to 60 or 70 |from 20 or 30 |inches wide. |
| |lode, Martin’s|feet; when |to 60 or 70 |The direction |
| |lode, and |united, it |feet, but is |of this vein, |
| |Glover’s lode.|varies from 8 |more commonly |is nearly |
| |In the united |or 10 to 20 or|from 40 to 50 |north and |
| |mines, the |30 feet. The |feet. The di- |south, its un-|
| |principal |branches are |rection of the|derlie is |
| |workings are |generally a- |vein, is |west, and a- |
| |upon the Old |bout 10 or 12 |north-west and|bout three |
| |lode, and a- |feet wide, and|south-east; |feet per fath-|
| |bout five or |the upper one |its underlie |om. Some of |
| |six others are|is most pro- |is south, and |the other |
| |more or less |ductive. |about five or |veins inter- |
| |productive. |The direction |six feet per |sect it. |
| |Numerous smal-|of the Veta |fathom. | |
| |ler lodes or |Grande, is | | |
| |“branches” oc-|from 30 to 40 | | |
| |cur also in |degrees south | | |
| |both mines. |of east, and | | |
| |The principal |north of west,| | |
| |lodes are from|and its under-| | |
| |2 or 3, to 7 |lie, from two | | |
| |or 8 feet |to three feet | | |
| |wide; the |per fathom | | |
| |“branches” are|south. Other | | |
| |generally 12 |veins of less | | |
| |or 18 inches |size, occur in| | |
| |wide. The di- |the neighbour-| | |
| |rection of the|hood of the | | |
| |lodes varies |Veta Grande, | | |
| |from nearly |which cross it| | |
| |east and west |at an acute | | |
| |to about 20 |angle. One of | | |
| |degrees north |these appears | | |
| |of east and |to heave the | | |
| |south of west.|vein for about| | |
| |The underlie |700 feet, be- | | |
| |of the princi-|ing the most | | |
| |pal lodes, is |remarkable de-| | |
| |from 2 to 3 |rangement of | | |
| |feet per fath-|the kind on | | |
| |om north, that|record. | | |
| |of the smaller| | | |
| |ones about the| | | |
| |same south. | | | |
| | | | | |
|Ores |Chiefly copper|Chiefly red |Sulphuret of |Argentiferous |
| |ore, occasion-||silver, na- |silver, native|sulphuret of |
| |ally native |tive silver, |silver, pris- |lead, native |
| |copper, blue |sulphuret of |matic black |silver, sul- |
| |and green car-|silver, and |silver, red |phuret of |
| |bonate of |argentiferous |silver, native|silver, red |
| |copper. Tin, |pyrites. |gold, argen- |silver. |
| |or oxide of | |tiferous | |
| |tin, also oc- | |galena. | |
| |curs, but not | | | |
| |in very great | | | |
| |abundance. | | | |
| | | | | |
|Produce |9-1/4 per |3-1/2 oz. per |Four ounces of|Six to seven |
|of the |cent. of fine |quintal. |silver per |ounces of sil-|
|ores |copper; aver- | |quintal of 100|ver per quin- |
| |age produce in| |lbs., equiva- |tal of 100 |
| |100 parts of | |lent to 2-1/2 |lbs. Equiva- |
| |ore. | |parts of metal|lent to from |
| | | |in 1,000 of |3-3/4 to 4-1/2|
| | | |ore, or 1/4 |parts of metal|
| | | |per cent. |in 1,000 of |
| | | | |ore, or from |
| | | | |3-8ths to |
| | | | |nearly 1/2 per|
| | | | |cent. |
| | | | | |
|Vein- |Chiefly |Chiefly |Quartz, ame- |Quartz, pearl-|
|stone |quartz, of |quartz, occa- |thyst, carbon-|spar, and cal-|
| |which many |sionally ame- |ate of lime, |careous spar. |
| |varieties oc- |thyst, carbon-|pearlspar, and| |
| |cur. |ate of lime, |hornstone. | |
| | |and sulphate | | |
| | |of barytes. | | |
| | | | | |
|Mineral |The ores are |The ores are |The ores are |The ores are |
|sub- |generally |generally |accompanied by|accompanied by|
|stances |accompanied by|accompanied by|blende, |blende, |
| |“gossan”[34] |blende, sul- |spathose iron,|spathose iron,|
| |in the backs |phuret of |copper and |and a little |
| |of the lodes, |antimony, and |iron pyrites. |iron and ar- |
| |by blende, and|iron pyrites. | |senical py- |
| |by iron, and | | |rites. |
| |arsenical | | | |
| |pyrites in | | | |
| |depth. | | | |
| | | | | |
|Depth of|_Woolf’s en-_ |_Tiro Gener-_ |_Tiro Gener- |_Franken- |
|the |_gine-shaft_, |_al_, 182 |al_, 310 fath-|schacht_, 180 |
|princi- |248 fathoms; |fathoms; |oms. |fathoms. |
|pal |Pearce’s _en-_|_Gallega_ | | |
|shafts |_gine-shaft_, |shaft, 138 | | |
| |275 fathoms. |fathoms. | | |
| |Some of the | | | |
| |other engine | | | |
| |shafts are | | | |
| |scarcely in- | | | |
| |ferior in | | | |
| |depth. | | | |
| | | | | |
|Depth of|At Woolf’s |There is no |There is no |The adit at |
|adit at |engine-shaft, |adit to this |adit to this |the shaft |
|the |13 fathoms. |mine. |mine. |called Fran- |
|princi- |The average | | |kenschacht is |
|pal |depth of the | | |47 fathoms in |
|shafts |adit at the | | |depth. |
| |other engine- | | | |
| |shafts is a- | | | |
| |bout 30 or 40 | | | |
| |fathoms. | | | |
| | | | | |
|Quantity|Varies from |About 80 gal- |The Valenciana|50 gallons per|
|of water|2,000 to 3,000|lons per min- |was a dry mine|minute. |
| |gallons per |ute. |from its com- | |
| |minute. | |mencement in | |
| | | |1760 to 1780, | |
| | | |when it first | |
| | | |became | |
| | | |troubled with | |
| | | |water, in con-| |
| | | |sequence of | |
| | | |some of the | |
| | | |workings being| |
| | | |inadvertently | |
| | | |communicated | |
| | | |with the ad- | |
| | | |joining mine | |
| | | |of Tepeyac; | |
| | | |which, al- | |
| | | |though upon | |
| | | |the same vein,| |
| | | |was extremely | |
| | | |wet. The quan-| |
| | | |tity of water | |
| | | |raised during | |
| | | |the late work-| |
| | | |ing appears to| |
| | | |have been a- | |
| | | |bout 110 gal- | |
| | | |lons per min- | |
| | | |ute, but the | |
| | | |regular influx| |
| | | |was much less.| |
| | | | | |
|Height |About 230 |On an average |310 fathoms. |133 fathoms. |
|to which|fathoms at the|about 150 | | |
|the |consolidated |fathoms. | | |
|water is|mines, at the | | | |
|raised |united mines, | | | |
| |about 110 | | | |
| |fathoms. | | | |
| | | | | |
|Power |9 steam-en- |Usually 10 |A steam-engine|Two water- |
|employed|gines; 3 of |malacates.[b] |of 30-inch |wheels, each |
|in |90-inch cylin-| |cylinder, and |42 feet in |
|drainage|der, 3 of 85, | |7 malacates. |diameter. |
| |1 of 80, and 2| | | |
| |of 65. A water| | | |
| |wheel, 48 feet| | | |
| |in diameter. | | | |
| | | | | |
|Probable|1,500 con- |32 horses con-|65 horses con-|16 horses con-|
|equiva- |stantly at |stantly work- |stantly at |stantly at |
|lent in |work, or a |ing, or a |work, or a |work or a |
|actual |total number |total number |total number |total number |
|horse- |of above |of about 100 |of about 200. |of about 50. |
|power |4,500. |horses.[c] | |[d] |
| | | | | |
|Average |12,700_l._ |20,000_l._ per|About |Cannot be as- |
|annual |taking the |annum.[c] |40,000_l._, |certained, but|
|expense |average of the| |per annum.[d] |evidently very|
|in |last ten | | |small.[d] |
|drainage|years.[a] | | | |
| | | | | |
|Quantity|16,400 tons of|21,380 tons of|32,500 tons of|630 tons of |
|of ore |copper ore, a |silver ore.[c]|silver ore.[d]|silver ore.[d]|
|annually|few tons of | | | |
|produced|tin ore.[a] | | | |
| | | | | |
|Produce |1,517 tons of |153,000 lbs. |221,900 lbs. |6,160 lbs. |
|in metal|fine copper, a|troy of sil- |troy silver. |troy of sil- |
| |little tin.[a]|ver.[c] |[d] |ver.[d] |
| | | | | |
|Total |119,800_l._[a]|423,400_l._ |About |About |
|returns,| |per annum.[c] |600,000_l._[d]|18,000_l._[d] |
|or value| | | | |
|of the | | | | |
|above | | | | |
| | | | | |
|Total |93,500_l._ ex-|252,170_l._ |197,900_l._ |9,500_l._ per |
|costs of|clusive of |per annum.[c] |per annum.[d] |annum.[d] |
|the mine|lord’s dues; | | | |
| |98,600_l._ in-| | | |
| |cluding lord’s| | | |
| |dues.[a] | | | |
| | | | | |
|Clear |21,000_l._ per|171,240_l._ |118,750_l._ |3,560_l._ per |
|profit |annum.[a] |per annum.[c] |per annum.[d] |annum.[d] |
|to the | | | | |
|proprie-| | | | |
|tors | | | | |
| | | | | |
|Amount |75,000_l._[a] |130,000_l._[c]|Cannot be as- |Cannot be as- |
|of | | |certained, but|certained, but|
|capital | | |known to have |probably very |
|invested| | |been very |small.[d] |
| | | |small.[d] | |
| | | | | |
|Interest|280 per cent. |Nearly 700 per|Not known, but|Not known, but|
|on |after paying |cent. after |certainly many|probably very |
|capital |back the orig-|paying back |hundred per |high.[d] |
|invested|inal capital. |the original |cent.[d] | |
| |[a] |capital.[c] | | |
| | | | | |
|Propor- |Costs exclu- |About 59-1/2 |Costs 60 per |Costs 73 per |
|tion of |sive of lord’s|per cent. |cent. In the |cent.[d] |
|costs to|dues, 78 per | |nine years | |
|returns |cent.[a] | |following, the| |
| | | |proportion was| |
| | | |80 per cent., | |
| | | |at the end of | |
| | | |that time the | |
| | | |working of the| |
| | | |mine was | |
| | | |stopped by the| |
| | | |revolution, in| |
| | | |the year 1809.| |
| | | |[d] | |
| | | | | |
|Number |About 2,500 |About 900, of |3,100 Indians |700 miners of |
|of men |persons, of |whom nearly |and Mestizoes,|whom 550 are |
|employed|whom about |600 are em- |of whom 1,800 |employed under|
| |1,450 are em- |ployed under |are employed |ground. |
| |ployed under |ground. |under ground. | |
| |ground. | | | |
| | | | | |
|Wages of|Probably about|About 8 or 9 |From 4 to 5 |About 1_s._ |
|the |3 shillings on|shillings per |shillings. |6_d._ per day.|
|mines |an average. |day. | | |
|per day | | | | |
| | | | | |
|Quantity| | |1,420 cwt.; |240 cwt.; |
|and ex- | | |value |value |
|pense of| | |15,830_l._ |1,070_l._ |
|powder | | | | |
| | | | | |
|Manner |Sold to the |Chiefly re- |Sold to the |Delivered to |
|in which|smelting com- |duced by the |Rescatadores, |the government|
|the ores|panies, and |company at the|and reduced by|reduction |
|are dis-|smelted by |hacienda of |smelting and |works in the |
|posed of|them at Swan- |Sanceda, by |amalgamation |neighbourhood |
| |sea, in South |smelting and |at haciendas, |of Freyberg, |
| |Wales. |amalgamation. |in the neigh- |where they are|
| | | |bourhood of |partly |
| | | |Guanaxuato. |smelted, and |
| | | | |partly amal- |
| | | | |gamated. |
+--------+--------------+--------------+--------------+--------------+
[a] Average of the last Ten Years.
[b] Malacate; a horse whim.
[c] Average of the last Six Years.
[d] Average year at the end of the Eighteenth Century.
[34] Gossan, or Gozzan; oxide of iron and quartz.