G6 CAEROLLITE. 



Name. From y^oi^;^oc^ straw, in allusion to 

 its colour. 



Carrollite, Faber. A copper-Linnasite, 

 composed of -6-u S + Co2 S^. Colour tin- 

 ■\vhite, inclining to steel-grey. Lustre me- 

 tallic, tarnished in some places. Streak iron- 

 Llack. Brittle. Fracture uneven ; subcon- 

 choidal in small fragments. H. 5-5. S.G. 4-58. 

 Analysis by Smith -^ Brush : 



Sulphur .... 40-94 

 Cobalt ..... 38-21 



Copper 17-79 



Iron 1*55 



Nickel 1-54 



Arsenic . . . .a trace 



100.03 



BB on charcoal emits strong odours of 

 sulphurous acid and arsenic, intumesces and 

 swells to a white, brittle, and magnetic 

 globule. 



Locality/. Finksburg, Carroll Co., Mary- 

 land, U.S., in a vein of Copper Pyrites. 



Name. After the locality, Carroll Co. 



Carton de Montagne, or Mountain 

 Pasteboard. A kind of Mountain Leather. 



Caryat. a synonym for Chalcedony. 



Cascholong, "^Brooke §• Miller. See Ca- 



CHOLONG. 



Cassiterite, Beudant, Dana. Oxide of 

 Tin. Pyramidal : primary form an obtuse 

 pyramid Avith a square base. It is found 

 in quadrangular prisms, terminated by four- 

 sided p}'ramids, and in many more complex 

 forms. Colour most commonly blackish- 

 brown, passing into black; also hair-brown 

 or reddish-brown, yellowish-green, yellowish 

 or greenish-white, and colourless. It varies 



Fig. 87. Fig. 88. 



from semi-transparent to opaque, the darker 

 varieties being opaque, while the lighter 



CASSITERITE. 



are translucent and semi-transparent. Oc- 

 curs massive, disseminated, in rolled pieces, 

 in grains as sand, but most frequently in 

 crystals, which are generally very indis- 

 tinct. Externally they are splendent. 

 Brittle. Fracture uneven or imperfect con- 

 choidal, with a shining resinous lustre. 

 Structure lamellar. Streak greyish-white, 

 H, 6 to 7. S.G. 6-8 to 7. 



Comp. 'Sn = tin 78-38, oxygen 21-62 = 

 100. 



Sometimes with small quantities of iron, 

 oxide of manganese, and tantalic acid. 

 Analysis from Finbo, by Berzelius : 

 Oxide of tin . . . .93-6 

 Tantalic acid . . . .2-4 

 Peroxide of iron . . .1-4 

 Peroxide of manganese . , 0-8 



98-2 



BB decrepitates, becomes pale, and is re- 

 duced where it rests on the charcoal. When 

 roasted it is converted into a grey oxide. 

 Insoluble in acids. 



Localities. — English. This ore is princi- 

 pally found in Cornwall, Aviiere it has been 

 worked from a very remote period. In 

 general, the Cornish crystals, though ex- 

 tremely perfect in form, are not of large 

 size, neither are they so ©ften macled as 

 those of Bohemia. Very tine crystals have 

 been found in the parish of St. Agnes, at 

 Trevaunance (Jigs. 87 and 88), at Polberro 

 Consols, and Huel Pye ; fine twinned crys- 

 tals at Beam, and other mines near St. 

 Austell ; and in large macled crystals at 

 Huel Gwinear. Beautiful crystals were met 

 with some years ago at the Wherry Mine, 

 near Penzance, and at St. Just. Foreign. 

 Galicia, in Spain : the Granite-hill of Puy 

 les Vignes, Haute Yienne, in France, and 

 near Hoc St. Andre', in Brittany; Pitka- 

 ranta, in Finland, in fine crystals ; Green- 

 land, at Evigtok, near Arksut, associated 

 with Cryolite and Tantalite ; Sweden ; 

 United States; Asia, on the east coast of 

 Sumatra; in the island of Banca, and on 

 the peninsula of Malacca ; Chili ; Xeres, in 

 Mexico ; Los Angelos, in California ; Austra- 

 lia, in the form of black sand. The com- 

 pound crystals come mostly from Bohemia 

 and Saxony. Some of the twin forms from 

 Zinnwald and Schlackenwald often weigh 

 several pounds. Splendid crystals are pro- 

 cured from Ijimoges. 



Name. From xoio-o-hiio;^ tin. 



Most of the tin of commerce is obtained 

 from this ore. 



Brit. Mus., Case 18. 



