A System of Instruction in the Practical Use of the Blowpipe Part 43

(3) on charcoal. Gives off fumes of a.r.s.enic, and fuses to a dark grey magnetic bead, very brittle, colors flame blue.

(4) in forceps. --

(5) in borax. As the preceding, but the cobalt being in large excess requires some time for its perfect oxidation, before the nickel reaction is exhibited.

(6) in mic. salt. Gives the cobalt reaction, and after the cobalt has been, removed that of nickel.

(7) with carb. soda. --

(8) Special reactions. As the preceding.

Mineral. Glance cobalt

Formula. CoS^{2} + CoAs.

Behavior

(1) in gla.s.s-bulb. --

(2) in open tube. As the preceding, but gives off more SO^{2}.

(3) on charcoal. Gives off S and As, and fuses to a magnetic bead. Colors flame blue.

(4) in forceps. --

(5) in borax. Gives a cobalt and slight iron reaction when treated as the preceding minerals.

(6) in mic. salt. As in borax.

(7) with carb. soda. Gives a sulphur reaction of silver.

(8) Special reactions. As the preceding.

Mineral. Nickel glance

Formula. NiS^{2} + NiAs.

Behavior

(1) in gla.s.s-bulb. Decrepitates and gives an orange colored sublimate of a.s.s^{2}.

(2) in open tube. As the preceding.

(3) on charcoal. As the preceding.

(4) in forceps. --

(5) in borax. As copper nickel.

(6) in mic. salt. Gives the nickel reaction occasionally somewhat obscured by cobalt.

(7) with carb. soda. As the preceding.

(8) Special reactions. As copper nickel.

Mineral. Ulmannite

Formula. NiS^{2} + Ni(a.s.sb)^{2}.

Behavior

(1) in gla.s.s-bulb. Gives a slight white sublimate of SbO^{3} and more or less a.s.s^{3}.

(2) in open tube. Gives off thick fumes of SbO^{3} and SbO^{5} with AsO^{3} and SO^{2}.

(3) on charcoal. As glance cobalt, but accompanied by dense fumes of SbO^{3}.

(4) in forceps. --

(5) in borax. As copper nickel.

(6) in mic. salt. As the preceding.

(7) with carb. soda. As the preceding.

(8) Special reactions. As copper nickel generally, but a.r.s.enic is not always present.

Mineral. Cobalt pyrites

Formula. ([,Co][,Ni][,Fe]) ([,,,Co=][,,,Ni=][,,,Fe=]).

Behavior

(1) in gla.s.s-bulb. When strongly heated gives off sulphur and becomes brown.

(2) in open tube. Gives off much SO^{2} and a small quant.i.ty of AsO^{3}.

(3) on charcoal. In the reducing flame small fragments fuse with the evolution of sulphur to a magnetic bead having a bronze colored fracture.

(4) in forceps. --