

COCCINITE. 





Nickel . 





. 1-79 



Copper 





. 1-39 



Arsenic 





. 70-37 



Bismutli 





. 001 



Sulphur 





. 0-66 



90 



99-88 



BB on charcoal, it gives off copious arseni- 

 cal fumes, and fuses to a white, brittle, 

 metallic globule, which, after being roasted, 

 imparts a blue colour to glass. 



Soluble in hot nitric acid, with separation 

 of arsenious acid. 



Localities. Cornwall: Botallack Mine, 

 in small particles, interspersed in reddish 

 Quartz and Chlorite. Has been found at 

 Dolcoath Mine, and was formerly Vv'orked 

 at Huel Sparnon and the Wherry Mine. 

 It is noAv worked at St. Austell Consols. 

 Foreign. — In large, well-defined crystals at 

 Tunaberg, Riddarhyttan and Kokensbii in 

 Sweden. Modum and Skutterud in Nor- 

 w^ay in mica-slate. Wehna in Sweden. 

 Querbach in Silesia. Siegen in Westphalia, 

 &:c. 



This ore of Cobalt and Smaltine furnish 

 the greater portion of the Smalt of com- 

 merce, which is employed in glass and 

 porcelain pamting, and for imparting a blue 

 tint to paper or linen. It is prepared by 

 roasting the ore, and then melting the oxide 

 of cobalt so pfoduced, in certain propor- 

 tions, with pure potash and pounded 

 quartz, which is afterwards ground to 

 powder and carefully washed : for the most 

 delicate purposes the oxide of cobalt is 

 employed as a pigment. 



Name. Kobolds in German are malicious 

 spirits haunting mines, and delighting in 

 mischief. The metal was named after them, 

 because its occurrence is unfavourable to 

 the ores more particularly sought for. 



Brit. Mus„ Case 12. 



M. P. G, Principal Floor, Wall-cases 9 

 (British); 20 (Foreign). 



CocciNiTE, Haidinger, is found in red- 

 dish-brown coloured particles on selenide of 

 mercurj^ at Casas Viejas, in Mexico. It 

 has an adamantine lustre, and resembles 

 Cinnabar, but the streak is paler than in 

 the latter mineral. 



Comp, Protiodide of mercury or Hg,I 

 = mercury 44-1, iodine 55-9 = 100'-0. 



BB fuses and easily sublimes. 



"It forms a magnificent Avater colour, 

 known by the name of Scai-let, which, 

 however, fades verj' quickly when exposed 

 to light, and at the same time destroys the 

 colour of vermilion which may be mixed 



COLLYRITE. 



with it. It is likewise used in calico- 

 printing."— Gmelin. ' 



CoccoLiTE, Jameson, is of two kinds, 

 white and green. Both are granular, friable 

 varieties of Pyroxene, the former of whicli 

 may be referred to the sub-species Diopside. 

 Coccolite consists of small, translucent 

 granules of irregular shapes, and of various 

 shades of green, which are very slightly 

 coherent, but sufficiently hard to scratch 

 glass. Lustre vitreous. Fracture lamel- 

 lar. S.G. 3-3. 



BB infusible alone. With carbonate of 

 soda it melts to an olive-green, vesicular, 

 slaggy glass; and with borax, to a pale 

 yellow semitransparent glass. 



It is chiefly found at the iron mines of 

 Sudermannland and Nerika in Sweden, and 

 of Avendal in Norway. 



Name from y.oxxo?, a grain. 



Brit. Mus., Case 34. 



Cochineal, Red Copper Ore, Kirwan. 

 See Red Copper, Tile Ore, &c. 



Cockle, Dufrenoy. See Tourimaltne. 



Cock's-comb Barytes. a variety of 

 Barytes formed of an aggregation of small 

 greyish-white and opaque crystals. It is 

 found in Cumberland, crystallized at Car- 

 rock Fells, and in curved plates at Patter- 

 dale : also in Derbyshire and Lancashire. 



Cock's-comb Pyrites. A form of Mar- 

 casite composed of a comb -like aggregation 

 of crystals similar in shape to Jig. 123. Oc- 

 curs in heaps of refuse (attle- heaps) at Huel 

 Crebor, near Tavistock, in Devonshire ; the 

 Harz, &c. 



Brit. Mus. Case G. 



Fig. 123, 



31. P. G. Horse-shoe Case, No. 151. 



Cog-wheel-ore, Nicol. See Radelerz. 



Coking Coal. The name given to those 

 kinds of Coal which can be used for making 

 Coke. For that purpose they should con- 

 tain little or no sulphur. 



Colestin, Haidinger, Hausmann, Nan- 

 mann, v. Kobell. See Celestlne. 



CoLLY'RiTE is a vcry soft, and Avhite 

 clay-like compound, with a glimmering 

 lustre, unctuous to the touch, and adhering 

 strongly to the tongue. H. 1 to 2. S.G. 

 2 to 2-15. 



Comp. Hydrated Disilicate of Alumina, 



or A12 Si + 10 H. 



