262 copper. 



crystals, or thin tab!es of a carmine red colour, which are some- 

 times aggregated into amorphous or scopiform flakes. The crys- 

 tals are translucent with an adamantine lustre. 



Ferruginous Red Copper, or Tile Ore, is of a reddish-brown 

 colour, lead-grey or blackish. It occurs massive, disseminated, 

 and incrusting copper pyrites. The lustre is dull or glimmering. 

 The fracture is earthy or imperfect flat conchoidal ; it yields easily 

 to the knife, and sometimes to the nail. 



Sp. 7. Blue Carbonate of Copper. Pl. XXXVI. fig. 1. — 

 Kupferlazur, Werner; Cuivre carbonate bleu, Haiti/. — Oxide of 

 copper combined with carbonic acid forms two species, the blue 

 and the green carbonate. Of the blue carbonate of copper there 

 are two varieties : — the radiated has an asure blue colour, which 

 often passes into blackish-blue, Berlin-blue, *and smalt-blue. It 

 occurs massive, imitative, in prismatic distinct concretions, and 

 very frequently crystalized. The crystals are minute, and generally 

 in the form of oblique four-sided prisms. Externally the lustre is 

 shining, in the massive and particularjextcrnal shapes dull; internally 

 between vitreous and resinous. The crystals are semi-transparent 

 or translucent. The fracture is small and imperfect conchoidal. 

 This ore is brittle and rather easily frangible. The specific gravity 

 varies from 3*2 to 3*6. It dissolves with effervescence before the 

 blowpipe. Its constituents are, copper 56, oxygen 14, water 6. 

 This mineral occurs in veins with other ores of copper, in Corn- 

 wall, in Scotland, and in many places on the continent. 



Earthy Blue Carbonate of Copper has a smalt-blue colour, and 

 occurs in friable incrustations or masses, composed of dull earthy 

 particles. 



Sp. 8. Green Carbonate of Copper, or Malachite. — Fas- 

 richter Malachat, Werner ; Cuivre carbonate vert, Ham/. — This 

 ore of copper is divided into two sub-species, viz. fibrous malachite 

 and compact malachite. Fibrous malachite, has an emerald- green 

 colour. It is seldom massive, sometimes disseminated, tuberose, 

 stalactitic, reniform, botryoidal, and in fibrous distinct concretions ; 

 but it is most commonly found forming an incrustation on the 

 surfaces of other ores. The fibres are slender scopiform, or stel- 

 lular, and the lustre is generally silky. It occurs also crystalized in 



