PYRARGYRITE. 



ture shining-conchoidal. H. 2 to 2-5. S.G. 

 2-7 to 2-9. 



Fig. 344. 



Comp. Af S + Sb S. 



Analysis, from Mexico, by Wohler : 

 Silver ..... 60-2 

 Antimony . . . .21-8 

 Sulphur .... 18-0 



100-0 



BB on charcoal, decrepitates slightly; 

 then fuses, giving off an odour of sulphur- 

 ous acid and antimonial fumes : and after 

 long blowing in the outer flame yields a 

 globule of pure silver. 



Soluble without effervescence in nitric 

 acid. 



Localities. — English. Cornwall ; at Huel 

 Brothers, Huel Duchy near Callington, 

 Herland Mine, Perran Mine, &c. — Foreign. 

 Chiefly at Andreasberg, in the Harz, with 

 Calc Spar, Native Arsenic, and Galena. 

 Kongsberg, in Norway, Freiberg, in Saxony. 

 Schemnitz, Kremnitz, Nagy- and Felso- 

 banya, in Hungary. Guadalcanal, in 

 Spain. Allemont, in Dauphiny. Ste. Marie- 

 aux-Mines, in the Vosges. The Pyrenees. 

 In S. America it is the source of immense 

 produce, the mine of Veta-Negra near Som- 

 brerete having yielded 700,000 marcs of 

 silver in the course of a very few months. 



Name. From ^v^, fire, and ^.^yv^o;, silver. 



Brit. Mus., Case 11. 



M.P.G. Principal Floor, Wall- cases 14 

 (British), 22 (Foreign). 



Pyrargyrite has been subdivided into two 

 varieties : Dark red Silver -ore, and Light red 

 Silver-ore (see Proustite), which may be 

 distinguished from each other by the colour 

 of the streak ; the dark red affording a co- 

 chineal-, or brick-red coloured streak, but 

 the light red ore an aurora coloured streak. 

 Jameson and Phillips disagree. 



Both varieties constitute valuable ores of 

 silver, and are occasionally found in masses 

 of considerable magnitude. 



P3Targyrite may be distinguished from 

 Cinnabar by inferior specific gravity, and by 

 yielding a globule of silver before the blow- 

 pipe, instead of volatilizing. Red Copper 

 Ore, for which it may sometimes be mis- 

 taken, has a lower specific gravity, and is 

 usually accompanied by Native Copper,, 

 Malachite, and Brown Iron-Ochre; while 



PYRITES. S05 



Red Orpiment and Copper Glance, to which 

 it bears a slight resemblance, have both 

 a lower specific gravity, and afford a differ- 

 ent streak, that of the former being yellow, 

 and of the latter blackish. 



Pyreneite, Jameson. Pyrenit, Werner. 

 A black or greyish-black variet}' of Iron^ 

 lime Garnet, occurring in small but very 

 symmetrical rhombic dodecahedrons, which 

 glisten externallv. Opaque. Fracture un- 

 even. Hard. S.G. 3-6 to 4; 



Locality. In limestone in, the Pic d'Eres- 

 lids, near Bareges in the Pyrenees (whence 

 the name Pyreneite.) 



Pyegom (from ^O^yu/jui, furnished with 

 toivers). A dingy green variety of Sahlite, 

 found in the Valfey of Fassa, in the Tyrol. 



Pyrite, Haidinger, Nicol. Pyrites, 

 Dana, Greg §- Leitsom. Cubical. Com- 

 monly occurs in cubes, either imbedded 

 singly or united into groups : often forming 

 spheroidal, botrvoidal or other aggregations, 

 with a crystalline surface. Frequently in 

 macles. Also radiated-fibrous and massive. 

 Colour a peculiar brass-yellow. Lustre 

 metallic-splendent. Opaque. Streak brown- 

 ish-black. Strikes fire with steel. Brittle. 

 Fracture conchoidal, uneven. When broken 

 emits a sulphurous smell, H. 6 to 6-5. S.G, 

 4-83 to 5-03, 



Fig. 348 



Comp. Bisulphide of iron, or Fe S^^iron 

 45-77, sulphur 64,23 = 100. 



BB burns with a bluish flame and a 

 strong smell of sulphur. In the reducing 

 flame fuses readily to a black magnetic glo- 

 bule, which is crystalline on the surface. 



Dissolves in concentrated nitric acid, leav- 

 ing a residue of sulphur. Scarcely acted on 

 by muriatic acid. 



' Localities. — English. Common in nearly 

 all metallic mines. Well crystallized in 

 Fowey Consols, Huel Maudlin, Huel Maria, 

 and Herodsfoot Mines, Cornwall. Virtuous 

 Lad}' Mine, Devonshire. Aust Passage, on 

 the "Severn, in sandstone. Alston Moor 



