COP

COP

( 318 )

II. Family. Oxvd or Copper.

Sp. II. Ruby Copper. Florid, red Copper ore,Kirw. Roth Kupfererz , Werner. Cuivre oxyderouge, Hauy.

Of this fpecies there are the following va-rieties.

Var. i. Lamellar R. C. Blattriges R. K.Werner.

Its colour is dark cochineal-red, incliningfometimes to lead-grey; when cryftallized it isolten of a full carmine-red. It occurs in mafs,difieminated and cryftallized.

1. In cubes.

2. In aluminiform octahedrons, either per-fect: or truncated on the angles or on the edgesand angles.

The cryftals are fmall and very fmall, andare often aggregated together by their fides;their furfaces are fmooth and filming. Theinternal luttre of this mineral is more or lefsfhining, and is intermediate between metallicand that of the diamond. Its fracture is im-perfectly foliated paffing into granular uneven.It occurs fometimes in granular diltinct con-cretions palling into the compact variety. Whenin mafs it is ufually opake or at molt tranflucenton the edges ; the cryftals are tranfp;irent, verg-ing into tranflucent. It gives a brownifh brick-red ftreak, is moderately hard, brittle and eafilyfrangible. Sp. gr. 3.95.

By expofure to the blowpipe on charcoal itjs eafily reducible to a metallic bead withoutemitting either odour or fmoak. It diflolves inthe nitrous and muriatic acids, in the formerwith and in the latter without effervefcence.According to the analyfis of Mr. Chenevix, itconfifts of 88.5 copper,

11.5 oxygen.

100.0

It is met with chiefly in veins, and appearsto be peculiar to primitive mountains : the fub-ftances with which it is accompanied are nativecopper, malachite, and brown iron ochre; fome-times mountain green, copper pyrites and otherores of this metal, alfo quartz, calcareous andheavy fpars.

It is found in Cornwall, in Hungary, Saxony ,the Hartz, Siberia, Peru and Chili.

Var. 2. Capillary R. C. Haarfcrrmiges R. K.Werner.

This variety differs from the preceding inbeing of a fomewhat lighter colour, fuperiorluftre, and being compofed of fmall capillarycryftals and thin flakes.

Var. 3. Compaft R.C. DichtesR.K. Wer.

It occurs in mafs and difieminated but nevercryftallized: its internal luftre is glimmering,femi-metallic. Its fracture is even, and it isopake. In other refpe&s it agrees with Var. x.

Sp. III. Tile-red Copper . Brick-red Copper,Kirw. Ziegelerz, Werner.

This fpecies is found in two ftates, induratedand earthy.

Var. 1. Indurated T. C. Fejles Z. Werner.Its colour is intermediate between hyacinthand brownifh-red, and pafles on the one handinto lead and dark fteel-grey, and on the otherinto blackifh or reddifh brown. It occurs maf-five and diffeminated. The reddifh kind has aglimmering luftre and flat conchoidal fracture,the browner kind has a fomewhat refinous luftreand fmall conchoidal fracture. It acquires aluftre by fri&ion, is moderately hard and brittle.

When expofed to the blowpipe it becomesblack and is infufible without addition. Borax is tinged by it of a dirty green. It appears tobe an intimate mixture of compact ruby copperwith brown iron ochre, and its produce of coppervaries from ten to fifty per cent.

It occurs in veins with ruby copper, mala-chite, copper pyrites and iron ochre. It paflesinto brown iron ftone.

Var. 2. Earthy T. C. Erdiges Z. Werner.Its colour is hyacinth-red, paffing into reddilhor yellowifh-brown. Its texture is between

friable and folid. It occurs in mafs, difiemi-nated, and incrufting copper pyrites. It is with-out luftre, has an earthy fratture and {lightlyfoils the fingers. In its other characters it agreeswith the preceding variety.

III. Family. Sulphuret of Copper .

Sp. IV. Vitreous Copper. Kupferglas, Wer.Cuivre vitreux, Broch. Cuivre Julfure, Hauy.

Its colour is dark lead-grey paffing into blackifhgrey, it often prefents a fuperficial fteel-colouredtarnifh. It occurs in mafs, difieminated, or cryf-tallized.

1. In cubes.

2. In octahedrons.

3. In hexahedral prifms, either regular orterminated by trihedral fummits placed on threeof the lateral fides.

The cryftals are fmall and very fmall. Ex-ternally they are fhining; internally they exhibita gliftening metallic luftre. The fracture isfine grained uneven, paffing into conchoidaland thence into even. It gives a fliining ftreak,is blackifh when pulverized ; commonly breaksfhort under the knife, and is eafily frangible.Sp. gr. 4- 1 5.4.