SI L ( 295 ) Sit
Silver Antim.
89 —
IX
Selb.
84 -
14
Klapr.
Thef
76 —
24
Do.
The c
77 —
23
Do.
From
78 —
22
Vauq.
From
75.25 —
24-75
Abich.
From
It occurs in veins of calcareous fpar andheavy fpar, accompanied by native filver, gale-na, and occafionally brown blende, iron pyrites,and grey copper.
It is found at Wittichen and Altwolfach, inthe territory of Fiirftenberg, at Andreafburgin the Hartz, and at Cafalla near Guadalcanal ,in Spain . f
Sp. 4. Arfenical Silver. Arfenik Silber,Germ. Argent Arfenical, Broch.
Its colour is tin-white, palling into light leadgrey; it is fuperficially tarnilhed yellowilh orfteel grey. It occurs in mafs, dilTeminated, infmall globular or kidney-fhaped maffes, orcryftallized: the forms of its cryftals are
1. The regular hexahedral prifm. Some-times it is fomewhat comprefled, or roundedon its lateral edges.
J2. An acute fix-fided pyramid with the fum-mit truncated.
Internally it is more or lefs fhining with ametallic luftre. Its frafture is fmall lamellar,either ftrait or curved. The maflive varietiesprefent fine grained diftinft concretions ; theglobular and kidney-fhaped are compofed ofthin curved concentric lamellae.
It acquires a luftre by friftion, is rather foftand brittle.
Before the blowpipe it melts, and the arfenicand antimony are volatilized; there remainsbehind an impure bead of filver.
A fpecimen analyfed by Klaproth confut-ed of
Iron - ... - 44.25
Arfenic - - - - 35.
Silver - - - - 12.75
Antimony - - - 4.
96.
It occurs in veins of calcareous fpar withnative arfenic, red and fulphuretted filver ores,galena, and blende.
It is met with at Andreafberg in the Hartz,and Altwolfach in Swabia .
®P* .5- Carbonated Silver. Calc form Silverere, Ktrw. Luftfaures Silber , Wid.
Its colour is greyifh pafling to iron black.It occurs in mafs or difieminated. Its luftre ismetallic, varying from glimmering to fhining.
ine-grained variety from Wolfach .oarfe-grained from Do.
Andreafberg.
Do.
Do.
Its frafture is fine-grained uneven, palling into'earthy. It acquires a polifh by friction. It isfoft, not very brittle, and of a high fpecificgravity.
It is fufible with eafe before the blowpipeinto a metallic globule. Its component parts,-according to Selb , are
72.5 Silver
12. Carbonic acid
15.5 Oxyd of antimony and a trace of copper
100.
It was found in 1788 at Altwolfach, in avein of heavy fpar, with native and fulphurettedfilver and grey copper.
Sp. 6. Hornfilver. Hornerz, Wern. Ar-gent come, Broch.
Of this ore there are the two followingfubfpecies.
1 Subfp. Common Hornfilver.
Its colour is pearl-grey, pafling on the onehand to milk white, and on the other to lead-grey and violet blue, fometimes, though rarely,it has an olive or leek green tinge. It occurs ■in mafs, dilTeminated, fuperficial, in roundifhhollow balls, and cryftallized in cubes andacicular cryftals. The cryftals are fmall andvery fmall, and varioufly aggregated. - Exter-nally it is more or lefs fhining; internally itvaries from fhining to gliftening, and has arefinous luftre. Its fracture is fine-graineduneven, palling into fiat conchoidal. It iscommonly tranllucent. It takes a polifh byfrift ion. It is very foft, duftile, and flexiblewhen in thin plates. Sp. gr. 4.74—4.80.
When heated on charcoal by the blowpipe,it enters into fpeedy fufion, at the fame timedifengaging a difagreeable odour, and affords aglobule of metallic filver. The maflive horuifilver of Saxony has been analyfed by Klaproth ,with die following refult.
67.75 Silver2i. Muriatic acid6. Oxyd of Iron1.75 Alumine0.25 Sulphuric acid
9 6 -7S