44 THE PROSPECTOR'S HANDBOOK. 



Tin White Cobalt, 



Crystallization octahedral, cubical, and dodecaho 



dral, &c. 



Breaks with uneven and granular fracture. 

 Colour tin white and greyish. 

 Streak greyish black. 

 H. 5-3; S.G. 6-4 to 7-2. 

 Composition cobalt and arsenic. 



Before the blowpipe it colours borax and other flnxef! bin*.. 

 Affords pink solution with nitric acid. 



Earthy Oxide. 



Usually massive. 



Colour blue black or black. 



H. 1 to 1-5; S.G. 2-2 to 2-6. 



Composition oxides of cobalt and mangancso. 



Cobalt Bloom. 

 Lustre pearly. 

 Colour peach red, crimson ; sometimes grey or 



greenish. 



Streak paler ; powder-lavender. 

 Composition per cent. oxide of cobalt, 37 '6; the 



remainder, arsenic and water. 



Gives off arsenical odour when heated. Behaviour with 

 fluxes in the B.F. same as other cobalt ores. 



In Great Britain cobalt ore is found in cavities in lime- 

 stone of the carboniferous age. In Norway and other 

 countries a variety of tin white cobalt is found in gneissic 

 and primitive rocks. In Germany deposits of cobalt are 

 found in limestone over copper slates. Cobalt and nickel 

 ores are often met with in the same lode. 



COPPER. 



If a specimen is supposed to contain copper, it should be 

 examined either by means of the blowpipe or chemicals. 



With carbonate of soda on charcoal before the B.F., nearly 

 any copper ore is reduced and a globule of metallic copper 

 obtained. Heated with borax or microcosmic salt in O.R, 

 there results a green bead when hot, a blue one whm cold. 

 Most copper compounds, when heated in the inLer Harne, 



