CHALCOPYRITE. 

 Water 22-58 



99-84 

 BB decrepitates strongly, the flame be- 

 ing coloured green by the detached parti- 

 cles ; in powder emits" arsenical fumes, and 

 passes into a spongy slag, after Avhich it 

 melts quietly into a black, brittle, slightl}^ 

 vitreou.s globule ; which, by a second fusion 

 with soda, affords a globule of metallic cop- 

 per. 



Soluble in acids and ammonia. 

 Localities. — English. Associated with Cu- 

 prite, Copper Pyrites, and Malachite, at 

 Ting-Tang and at Huels Gorland, Muttrell 

 and Unity, in Gwennap; Huel Tamar, and 

 Gunnis Lake near Calhngton. — Foreign. 

 Crystallized in Iron-ore at Sayda in Saxony ; 

 in minute crystals at Herrengrund in Hun- 

 gary ; Moldawa in the Bannat. 



Name. From x«''^^«»'' copper, and <pvXXov, 

 a leaf, in allusion to the ease with which the 

 crystals may be separated into laminae like 

 Mica. 



Brit. Mus., Case 56. 



31. P. G. Principal Floor, Wall -case 2 

 (British). 



Chalcopyrite, Beudant, Greg §' Lettsom. 

 Copper Pyrites. Pj'ramidal ; tetrahedral. 

 The crystals present the general form of 

 the tetrahedron or spheroid, having the 

 solid angles alwaj's replaced. Their struc- 

 ture is perfectly lamellar, affording brilliant 

 surfaces parallel to the planes of a some- 

 what acute octahedron with a square base. 

 It also occurs stalactitio, botryoidal, mara- 

 millated, and amorphous; these are all 

 harder than the crystallized varieties. Colour 

 brass-yellow, often with a variegated tar- 

 nish. Lustre metallic. Streak greenish - 

 black. Fracture most commonlv uneven. 

 Opaque. H. 3-5 to 4. S.G. 41 to 4-3. 



Fig. lOi. 



Fig. 102. 



Camp. CuS FeS = copper 34-78, iron 30-47, 

 sulphur 34-78 = 100. 



Analysis from Ramberg, in Sayn, by H. 

 Rose ; 



Sulphur . . . , . 35-87 



Copper 34-40 



Iron . . . . . 30-47 

 Quartz matrix . . . 0-27 



101-01 



CHALCOTRICHITE. 73 



BB on charcoal emits sulphurous fumes, 

 and melts in a brittle, black globule, which 

 is magnetic. With borax yields pure cop- 

 per. 



Forms a green solution in nitric acid,, 

 leaving a residue of sulphur. 



Localities. British. — Cornwall, associated 

 with Erubescite, Grey Copper, Galena, and 

 Blende; Devonshire, at Huel Friendship, 

 near Tavistock ; Staffordshire, at the Ec- 

 ton mine ; Lancashire, at Bole Gap and 

 Coniston tinited mines (fg. 101); Alston 

 Moor, in Cumberland (_fig. 102) ; in many 

 places in Wales and Scotland, and in several 

 counties in Ireland. Auriferous Copper P}-- 

 rites has been met with at Goldscope mine, 

 near Keswick, in Cumberland, and argen- 

 tiferous, containing 27 ounces of silver to the 

 ton, at Gurtnadyne mines, in Tipperary. — 

 Foreign. Pyrenees ; Canada, south side of 

 Echo Lake, and north of the mouth of the 

 Root River. 



Name. From ;i:«'^'=«o»', copper, and pyrites. 

 Brit. Mus., Case 7. 



3LP.G. Principal Floor, Case 15, Wall- 

 cases 3 to 7, and 25 to 27 (British) ; 16 and 

 17 (Foreign) ; 40 (Jamaica). 



Chalcopyrite may be distinguished from 

 gold b}' its brittleness and want of mal- 

 leability, as well as by its fracture, which is 

 uneven or imperfectly foliated, whereas gold 

 has a hackly fracture. It differs from Iron 

 Pyrites, which it often greatly resembles, 

 by inferior hardness, and by yielding to the 

 knife, whereas Iron Pyrites gives lire with 

 steel ; its colour is also generally of a 

 deeper yellow than that of Iron Pyrites, 

 wiiich is more like brass in appearance; 

 hence its ricliness may be judged of by the 

 colour. The softer varieties, of a fine yellow 

 colour, which yield readily to the hammer, 

 contain the largest quantity of copper ; while 

 the harder and paler varieties are poor, from 

 the admixture of Iron Pyrites. 



Though a poor ore, it is the most 'abun- 

 dant, nearly one- third of all the copper ob- 

 tained by metallurgical operations being 

 extracted from it. 



Chalcosine, Greg §- Lettsom ; Chalko- 

 SINE, Beudant, v. Kobell. From %«A«o?, cop- 

 per. See Copper Glance. 



Chalcostibite, Glocker. See Wolfs- 



BERGITE. 



Chalcotrichite, Glocher. A fibrous 

 variety of Cuprite, or Red Copper, which 

 generally occurs in grouped or i-eticulated, 

 fine capillary crystals. These have been 

 referred by Brooke to the cubical sys- 

 tem, the slender fibres being elongated 

 cubes; while Kengott attributes them to 



