OHES OF COPPER. 139 



Olivenite. — Hydrous Copper Arsenate. 



Trimetric. I A 1=92° 30'. In prismatic crystal s, and 

 also fibrous and granular massive. Olive-green, and of 

 other greenish shades, to liver aud wood-brown. Streak 

 olive-green to brown. Substransparent to opaque. Brittle. 

 H.=3. G. =4-1-44. 



Composition. Cu 4 9 As 2 = Arsenic pentoxide 40 -6G> copper 

 oxide 56*15, water 3*19 = 100. Fuses very easily, coloring 

 the flame bluish green. B.B. fuses with deflagration, giv- 

 ing off arsenical fumes, and affords a brittle globule, which 

 with soda yields metallic copper. 



Obs. From Cornwall, the Tyrol, Siberia, Chili, and other 

 places. 



Besides the above, there are the following salts of copper : 



Copper Arsenates. — Euchroite has a bright emerald-green color, and 

 contains 33 per cent, of arsenic acid, and 48 of oxide of copper ; occurs in 

 modified rhombic prisms ; H =8*75 ; G=c>*4 ; from Li.beth.en, in Hun- 

 gary. Clinoclnsite \ApJmnesite) is of a dark verdigris-green inclining to 

 blue, and also dark blue; H. =2 5-3; G. =419-4*30. it contains 62,'t per 

 cent, of copper oxide ; from Cornwall. Erinite has an emerald-green 

 color, and occurs in mammillated coatings ; H. =4*5-5 ; G.=4"04; con- 

 tains 594 per cent, of copper oxide ; from Limerick, Ireland. Liroco- 

 nit varies from sky-blue to verdigris-green ; occurs in rhombic prisms, 

 sometimes an inch broad ; H. =2-^*5; G.=3'8-~*98* Chcdcophyttiti 

 [copper mica) is remarkable for its thin foliated or mica-like structure- 

 color emerald or grass-green ; H.=2 ; G. =2*55. Contains 58 per cent, 

 of copper oxide ; from Cornwall and Hungary. Tyr elite {Copper 

 froth) is another arsenate of a pale apple-green and verdigris-green 

 color ; it has a perfect cleavage ; it contains 43 9 per cent, of copper 

 oxide ; from Hungary, Siberia, the Tyrol, and Derbyshire. Cornicall- 

 ite and G/ilor 'til , are names of other copper arsenates. These dif- 

 ferent arsenates of copper give an alliaceous odor when heated on 

 charcoal before the blowpipe. 



Copper Phosphates. — PseudomalacJiite (Phosphodialcite, Ehlite, Di 

 hydrUe) occurs in very oblique crystals, or massive and incrusting, and 

 has an emerald or blackish-green color; H.=4 5-5 ; G. =434 ; contains 

 64 to 70 per cent, of copper oxide ; from near Bonn, on the Rhine, and 

 also from Hungary. Libethenite has a dark or olive-green color, and 

 occurs in crystals, usually octahedral in aspect, and massive ; H. = 

 4; G. =3*6-3*8; contains 66*5 per cent, of oxide of copper; from 

 Hungary and Cornwall. Other copper phosphates are Veszrfyite, 

 TagUite, Isoclasite. Torbemite is a copper-and-uranium phosphate. 

 These phosphates give no fumes before the blowpipe, and have the 

 reaction of phosphoric acid. 



Copper Vanadates — Volborthite is a copper-and-calcium vanadate 

 from the Urals ; and Mottrarnmite and Psittacinite, copper-and-lead 

 vanadates, the former from England, and the latter from gold mines 

 in Silver Star district, Montana. 



Rivotite. Yellowish-green copper antimonate and carbonate. 



