Part 57 (1/2)

(5) in borax. The residual slag obtained on the charcoal gives an iron and copper reaction.

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

(7) with carb. soda. The silver is reduced and the antimony pa.s.ses off in dense fumes. The fused alkali gives the sulphur reaction on silver.

(8) Special reactions. --

Mineral. Pyargyrite

Formula. [,Ag]^{3}[,,,Sb].

Behavior (1) in gla.s.s-bulb. Sometimes decrepitates, fuses readily, and, when strongly heated, gives a red sublimate of SbS^{3}.

(2) in open tube. As in the preceding.

(3) on charcoal. Fuses with much spirting and covers the charcoal with antimonial fumes. When the residual AgS is heated for some time in the oxidizing flame, a bead of pure silver is obtained.

(4) in forceps. --

(5) in borax. --

(6) in mic. salt. --

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

(8) Special reactions. --

Mineral. Proust.i.te

Formula. [,Ag]^{3}[,,,As].

Behavior

(1) in gla.s.s-bulb. Fuses and at a low red heat affords a small sublimate of a.s.s^{3}.

(2) in open tube. Gradually heated it gives off AsO^{3} and SO^{2}. Sometimes also antimony fumes.