52 Mr. J. 'Napi'er on Cojyp^ Smelting. 



Burra forming a vein between black oxide, gave — 

 Red oxide . . . 93-5 

 SiHca .... 5-2 

 Oxide of iron . . 1"1 



99-8 

 A specimen from Chili diffused through carbonate of lime, 

 gave — 



Red oxide .... 48-3 

 Carbonate of lime . 48*5 

 Oxide of iron ... 1*2 

 Silica 1-3 



99-3 

 The colom* of this mineral is a rich red : the lime is mecha- 

 nically mixed, and can be seen by the microscope. 



There is another red ore which we have seen in considerable 

 quantity, resembling much the red oxide in appearance, only 

 wanting in lustre and specific gravity ; it generally occurs mas- 

 sive, having occasionally fine red veins through it. A specimen 

 from Cornwall gave — 



Oxide of copper . . 24' 8 

 Peroxide of iron . . 51*5 



Silica 19-0 



Water 4-1 



99-9 



These two would rank as tile ore from the colour, but would 

 produce excellent copper. 



Carbonates of Copper are of two kinds, blue and green, and 

 are very easily distinguished by their appearance ; or they may 

 be easily tested by effervescing when put into an acid. The 

 blue carbonate is of a deep azure ; when crystallized, the azure 

 blue is permanent ; but when massive, the colour is much paler, 

 especially when dry, becoming very rich and deep when moistened. 

 This ore may be easily distinguished from the blue vitreous ore 

 from the colour being more intense; it is also softer when 

 scratched with a knife. 



