Ores of Antimony.

247 G. III. Salts. Sulphat of ginc.

248 G. 1. Alloys Native antimory. *Kirw. ii. 245.

249 G. II. Sul. phurers. Grey ore of anti

mony.

247.

Pariety a. Compact calamine. Colour different shades of grey; fometimes yellow or brownish red. Luftre o. Opaque. Texture com. pact.

Variety 3. Striated calamine.

This variety alone is found cryftallized; but, like the others, it is also often amorphous. Colour white, and also various shades of grey, yellow, and red. Some what transparent. Texture ftriated. Luftre 2 to 1. GENUS III. SALTS OF ZINC. SPECIES I. Sulphat of zinc.

ORDER X. ORES OF ANTIMONY.

ANTIMONY is much ufed to give hardnefs to thofe metals which otherwise would be too foft for eertain purposes: printers types, for inftance, are compofed of lead and antimony. It is used alfo in medicine.

Ores of antimony are found abundantly in Germany, Hungary, France, Spain, Britain, Sweden, Norway, &c. They often accompany galena and hæmatites. They are found both in the fecondary and primitive stratified mountains. Their gangue (o) is often quartz and fulphat of barytes.

GENUS I. ALLOYS OF ANTIMONY.

SPECIES 1. Native antimony *. This mineral, which was firtt discovered by Dr Swab, has been found in Sweden and in France, both in maf ses and kidney-shaped lumps. Colour white, between that of tin and filver. Luftre metallie. Texture folia ted. Hardness 6. Sp. gr. above 6. Deflagrates with nitre. Before the blow pipe melts and evaporates, depofiting a white oxyd of antimony.

It confifts of antimony, alloyed with 3 or 4 per cent. of arfenic.

GENUS II. SULPHURETS OF ANTIMONY,
SPECIES I. Grey ore of antimony

This ore, which is the most common, and indeed almolt the only ore of antimony, occurs both maffive,

Kirw. ii. diffeminated, and cryftallized. Its cryftals are four-fided prifms, fomewhat flattened, whofe fides are nearly rectangles, terminated by mort four-fided pyramids, whofe fides are trapeziumst. Sometimes two of the edges are wanting, which renders the prifmn fix fided‡.

+ Romé de Lifle, iui.

49

Ibid. See

Four, de Min. No xxxii. 606.

Colour grey. Luftre metallic. Streak grey, me. alfo Hauy, tallic, and brighter. Powder black or greyish black. Hardness 6 to 7. Sp. gr. from 4.1327 to 4.516. Often ftains the fingers. Before the blow pipe melts Brion. eafily, burns with a blue flame, and depofits a white oxyd on the charcoal. When placed in an open veffel, over a flow fire, the fulphur evaporates, and leaves a grey oxyd of antimony. This oxyd, if fufed with tartar, is reduced.

This ore, when taken out of the mine, almost always

and carthy. Slightly ftains the fingers.

Variety 2. Foliated fulphuret.

Colour light feel grey. Luftre 3 to 4. Texture foliated. Powder as that of the laft variety.

Variety 3. Striated fulphuret.

Colour dark feel grey, and light bluish grey; furface often tarnifhed, and then it is dark blue or purplish. Luftre 3 to 2. Texture ftriated. Powder greyish black. This variety alone has been hitherto found crystallized.

250 Plumofer antimonial

ore.

SPECIES 2. Plumofe antimonial ore t. Sulphurets of antimony and arfenic. This fpecies, which is fometimes found mixed with+Kirav.ji. the cryftals of fulphurated antimony, is in the form of 250. brittle, capillary, or lanuginous cryftals, often fo finall that they cannot be diltinctly feen without a microfcope.

Be

brown or greyish black. Luftre 1, femimetallic. Colour fteel or bluish grey, often tarnished, and then fore the blow-pipe emits a smoke, which depofits a whitifh and yellowift powder on the charcoal: it then melts into a black flag.

It is fuppofed to confift of fulphur, antimony, arfenic, and fome filver.

SPECIES 3. Red antimonial ore +.
Hydrofulphuret of antimony.

258 Red anti

monial ore.

This fpecies is generally found in cavities of fulphu-+ Kirw. iia rated antimonial ore. It is cryftallized in delicate 250. needles, often diverging from a common centre.

the blow-pipe melts eafily, and evaporates with a fulColour red. Luftre 2, filky. Sp. gr. 4.7. Before phureous fmell.

This ore has not been analyfed. Mineralogifts have fuppofed it to be a natural kermes. If fo, we may conclude, from the experiments of Berthollet, that it is * Ann. de pofed of oxyd of antimony, fulphur, and fulphurated 259. a hydrofulphuret of antimony, and confequently comhydrogen gas.

GENUS III. OXYDS OF ANTIMONY.

Ores f Bifmuh.

253

GENUS IV. SALTS OF ANTIMONY.
SPECIES 1. Muriat of antimony:

This ore, which has been found in Bohemia, is fome. GIV. Sa'ts times in quadrangular tables; fometimes in acicular cryMuriat of ftals grouped like zeolites; and fometimes in prifms. antimony. Colour pale yellowish or greyish white. Luftre 3 to *Kirw. ii. 1, nearly metallic. Tranfparency 2. Texture foliated. Melts eafly by the flame of a candle, and emits a white vapour. t. Before the blow pipe decrepitates; when powdered, and just ready to melt, it evaporates, and leaves a white powder around. Between two pie ces of coal it is reducible to a metallic ftate.

251.

+ Hauy, Four, de Min. N°

xxxii. C09.

254

G. 1. Alloys. Na tive bifmuth.

264.

It has been found only in the primitive monntains, and is by no means common. When unaccompanied by any other metal, it does not form veins, but kidneyform maffes. It often accompanies cobalt. Its gangue is commonly quartz. Its orcs are not very abundant. They have been found chiefly in Sweden, Norway, Tranfylvania, Germany, France, and England

GENUS I. ALLOYS OF BISMUTH. SPECIES 1. Native bifmuth *. This mineral, which is found at Schneeberg, Johan*Kirw. ii. georgenftadt, &c. in Germany, has commonly the form of fmall plates lying above one another. Sometimes it is cryftallized in four-fided tables, or indiftinct cubes. Colour white with a fhade of red; furface often tarnifhed red, yellow, or purple. Luftre metallic, 3 to 2. Opaque. Texture foliated or ftriated. Hardness 6.♦ Briffon. Sp. gn 9.022 to 9.574. Exceedingly fufible. BeKirwan, fore the blow pipe gives a filvery white bead, and at laft evaporates in a yellowish white fmoke, which is depofited on the charcoal.

-255 G. II. Sulphurets. Common

fulphuret

It is generally accompanied by cobalt, and fometimes

contains arfenic.

GENUS II. SULPHURETS OF BISMUTH. SPECIES 1. Common fulphuret of bismuth*. This ore, which is found in Swede, Saxony, and of bismuth. Bohemia, occurs fometimes in amorphous mafles, and Kirw.. fometimes in needleform crystals. 266.-Sage, Mem. Par. 1782,307.

Colour commonly bluish grey, fometimes white; furface often tarnished yellow, red, and purple. Powder black and fhining. Luftre metallic, 2 to 3. Streak obfcurely metallic. Texture foliated. Harduefs 5. Kirtan Brittle. Sp gr. 6.131 to 6.4672. When held to Briffon. the flame of a candle, it melts with a blue flame and

fulphureous fmell. Before the blow-pipe emits a reddish yellow smoke, which adheres to the charcoal. This powder becomes white when it cools, and refumes its former colour when the flame is directed upon it*.

This ore, according to Sage, contains Go bifmuth, And, according to La Perouse, it holds 36 fulphur.

99

ORDER XII ORES OF ARSENIC.

ARSENIC is ufed as an alloy for feveral other metals, efpecially copper. It is fometimes employed to facilitate the fufion of glass, or to render it opaque, in order ployed as paints; and, like most other violent poifons, to form an enamel. Preparations of arfenic are em

it has been introduced into medicine.

This metal is fcattered in great abundance over the mineral kingdom, accompanying almoft every other metal, and forming alfo fometimes peculiar veins of its own. Of course it occurs in almost every fpecies of mountain, and is accompanied by a variety of gangues.

257 G.I.A. Native ar

GENUS I. ALLOYS OF ARSENIC. SPECIES 1. Native arfenic †. This mineral is found in different parts of Germany.fen It occurs generally in maffes of various fhapes, kidney. Kræ, ä form, botryoidal, &c.

255

Colour that of fteel. Its furface quickly becomes tar. nished by exposure to the air. Luitre metallic (when fresh), 3 to 2. Streak bluish grey, metallic, and bright. Powder dull and black. Texture compact. Hardnefs. 7 to 8. Brittle. Brittle. Sp. gr. 5.67† to 5.7249‡. Givest Kin an arfenical fmell when truck. Before the blow-pipe Br emits a white smoke, diffufes a garlic fmell, burns with a blue flame, gradually evaporates, depofiting a white powder.

It is always alloyed with fome iron §, and often contains filver, and fometimes gold.

GENUS II. SULPHURETS OF ARSENIC.'
SPECIES 1. Orpiment (P).
Auripigmentum.

This ore, which is found in Hungary, Wallachia, Georgia, and Turkey in Afia, is either maffive or cryftallized. The cryftals are confufed, and their figure cannot be easily determined; fome of them appear octohedrons, and others minute four fided prifins.

a

Ores of Nickel. 264

acids and by ammonia. The acid folution is the alkaline blue.

green;

Metallic Ores.

SPECIES 2. Brown cobalt ore*. Colour greyish or dark leather brown. Streak bright. or, unctuous. Communicates a pale blue tinge in fu.

Brown co. fion. balt ore.

* Kiru. ii.
276.
265
Yellow co

balt ore.
+Ibid.

266 G. IV. Salts.

Arfeniat of cobalt.

Jd. 278.

257 6.1. Sulphurets. Sulphuret of nickel with arfe. mic and iron.

Ibid. 286.

Brison.

268 GILOxyls. Nicke

ochre.

*Kirw. ii.

384.

SPECIES 3. Yellow cobalt ore +.
Colour yellow. Dull and earthy. Hardness 4 to 5.
Texture earthy. Streak brighter, unctuous. Gives a
weak blue tinge.

GENUS IV. SALTS OF COBALT.
SPECIES . Arfeniat of cobalt ‡.
Red cobalt ore.

This fpecies, like most other ores of cobalt, bas neither been accurately defcribed nor analyfed.

It is found in maffes of various fhapes, and cryftallized in quadrangular tables or acicular prifms.

Colour red. Luftre from 2 to 3, fometimes o. Tranf. Before parency o to 2. Hardness 5 to 7. Brittle. the blow pipe becomes blackish grey. Diffufes a week arfenical fmell. Tinges borax blue.

ORDER XIV. ORES OF NICKEL.

HITHERTO nickel has been found in too fmall quan tities to be applied to any ufe; of course there are, properly speaking, no mines of nickel. It occurs only (as far as is yet known) in the fecondary mountains, and it commonly accompanies cobalt. It has been found in different parts of Germany, in Sweden, Siberia, Spain, France, and Britain.

GENUS I. SULPHURETS OF NICKEL. SPECIES 1. Sulphuret of nickel with arsenic and iron. Kupfer nickel.

This, which is the most common ore of nickel, occurs either maffive or diffeminated, but never crystalli. zed.

Colour often that of copper, fometimes yellowifh white or grey. Recent fracture often filver white. Luftre metallic, 2 to 3. Texture compact. Hardness 8. Sp. gr. 6.6086 to 6.6481‡. Soluble in nitric and nitro-muriatic acids. Solution green. Before the blowpipe exhales an arfenical smoke, and melts into a bead which darkens by exposure to the air.

It is compofed of various proportions of nickel, arfenic, iron, cobalt, fulphur; often contains bifmuth, and fometimes filver and copper.

This mineral occurs either in the form of a powder, or indurated, and then is either amorphous, or cryftallized in acicular form cryftals. The powder is generally found on the furface of other nickel ores.

Colour different fhades of green. Luftre to o. Texture earthy. Sp. gr. confiderable. Slowly diffolves in acids: folution green. Before the blow-pipe does not melt; but gives a yellowish or reddish brown tinge to borax.

This ore often contains fulphat of nickel, which is ..foluble in water. The folution, when evaporated, gives oblong rhomboidal cryftals, from which alkalies preci pitate a greyish green oxyd. This oxyd is foluble by

ORDER XV. ORES OF MANGANESE (2).

HITHERTO manganefe, in its metallic ftate, has scarce. ly been put to any ufe; but under the form of an oxyd it has become of great importance. The oxyd of manganefe has the property of rendering colourless a variety of bodies which injure the tranfparency of glafs; and it has been long used in glass manufactories for this purpofe under the name of glafs foap. By means of the same oxyd, oxy muriatic acid is prepared, which has rendered manganele of great importance in bleaching. Not to mention the utility of manganefe to the chemift, the property which it has of facilitating the oxydation of other metals, and of rendering iron more futible—will probably make it, in no very remote period, of very confiderable importance in numerous manufactories.

nickel. + Kirgi 285

Ores of manganese occur often in ftrata, both in the primitive and fecondary mountains; scarcely ever, however, we believe, in those mountains which are confidered as the most ancient of all. They are very common, ́ ́ having been found abundantly in Germany, France, Spain, Britain, Sweden, Norway, Siberia, and other

countries.

270

G.I. Ory

277

GENUS I. OXYDS OF MANGANESE. Hitherto manganefe has only been found in the ftate of oxyd. La Peroufe, indeed, fufpected that he had found it in a metallic ftate: but probably there was fome mistake or other in his obfervations. SPECIES 1. Oxyd of manganese combined with barytes. Oxyd ef This fpecies, which exits in great abundance in Romance maneche near the river Soane in France, is found masfive, forming a ftratum in fome places more than 12ry tos. feet thick.

Colour greyish black or brownish black, of great intenfity. Luitre, external, o; internal, metallic, 1. Soon tarnishes by expofure to the air, and then becomes intenfely black. Texture granular. Fracture uneven; fometimes conchoidal. Often porous. Hardness 11. Difficultly frangible. Sp. gr. from 3.950 to 4.10. Abforbs water. When taken out of water after a minute's immerfion, it has a ftrong argillaceous smell. Conducts electricity nearly as well as if it were in a metallic ftate‡. Infufible by the blow-pipe. Tinges foda red; the colour difappears before the blue cone of flame, and is reproduced by the action of the yellow flame.

From

comiced

with ba

GENUS I. OXYDS OF TUNGSTEN. SPECIES 1. Wolfram (R). Oxyds of tung flen, iron, and manganefe-Tunghat of iron and manganefe.

Four. de Phyf. xxxie

22.

276

G I. Oxyds. Wolfram.

*

xix. 8.

This fpecies is found in different parts of Germany, in Sweden, Britain, France, and Spain; and is almost It occurs both conftantly accompanied by ores of tin. maffive and cryftallized. The primitive form of its cryftals, according to the obfervations of Mr Hauy, is a rectangular parallelopiped, whose length is 8.66, whose ‡ Fig. 42. breadth is 5, and thickness 4.33*. It is not common, Jour. de breadth is 5, and thickness however, to find cryftals of this perfect form; in many Min. N° cafes, the angles, and fometimes the edges, of the cryftal are wanting; owing, as Mr Hauy has fhewn, to the Fig. 43. fuperpofition of plates, whofe edges or angles decrease according to a certain law †. + Four. de Colour brown or brownifh black. Streak reddish Min. Ne xix. 8. brown. Powder ftains paper with the fame colour. Luftre external, 2; internal, 2 to 3; nearly metallic. Texture foliated. Eafily feparated into plates by percuffion. Hardness 6 to 8. Sp. gr. from 7.006 to* Kirwan. 7.333 . Moderately electric by communication. Not Hauy. magnetic. Infufible by the blow-pipe. Forms with borax a greenish globule, and with microcosmic salt a tranfparent globule of a deep red ¶.

Vauquelin,

The fpecimen of this ore examined by Meffrs d'El- Jour. de huyarts, was compofed of 65 oxyd of tungften,

22 oxyd of manganefe,

13 oxyd of iron.

100

Another

Min, No

XX. II.