A System of Instruction in the Practical Use of the Blowpipe Part 53

(7) with carb. soda. With much of the alkali is decomposed, yielding metallic copper. With small portions successively added first fuses and then intumesces, fuses with a strong flame, and is then absorbed into the charcoal, leaving metallic copper.

(8) Special reactions. Gives the phosphoric acid reaction.

Mineral. Olivenite

Formula. [.Cu]^{4}([.....As][.....P]) + [.H].

Behavior

(1) in gla.s.s-bulb. Gives off water.

(2) in open tube. --

(3) on charcoal. Fuses with detonation and the evolution of a.r.s.enical fumes to a brittle regulus, brown externally and having a white fracture.

(4) in forceps. Fuses and colors the outer flame green. On cooling has a crystalline surface.

(5) in borax. Gives the copper reaction.

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

(7) with carb. soda. Is reduced, yielding metallic copper.

(8) Special reactions. Gives the a.r.s.enic reactions.

ANTIMONY.

Mineral. Native antimony

Formula. Sb.

Behavior

(1) in gla.s.s-bulb. Fuses and, when strongly heated, volatilizes being redeposited in the tube as a dark grey sublimate.

(2) in open tube. Fuses and gives off dense white fumes, which are partly redeposited on the tube.

Sometimes also gives off a.r.s.enical fumes in small quant.i.ty.

(3) on charcoal. Fuses and gives off dense white fumes, which thickly incrust the charcoal and color the flame blue immediately beyond the a.s.say.

(4) in forceps. --

(5) in borax. The oxide formed upon charcoal gives the antimony reactions.

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

(7) with carb. soda. --

(8) Special reactions. The incrustation on the charcoal, if treated with nitrate of cobalt a.s.sumes the characteristic green color.

Mineral. Grey antimony

Formula. SbS^{3}.

Behavior

(1) in gla.s.s-bulb. Fuses readily and occasionally gives off a small quant.i.ty of sulphur. Strongly heated forms a brown sublimate of SbS^{3} and SbO^{3}.

(2) in open tube. Fuses and gives off SO^{2}, which pa.s.ses off up the tube, and dense white fumes of SbO^{3} and SbO^{5} which are partly deposited in the tube.

(3) on charcoal. Fuses and is partly absorbed by the charcoal and partly volatilized, incrusting the charcoal with the characteristic white oxides. Colors the flame blue.

(4) in forceps. --

(5) in borax. As the preceding.

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

(7) with carb. soda. Fuses and is reduced, yielding metallic antimony, which behaves as the preceding mineral upon charcoal. The alkaline ma.s.s gives the sulphur reaction.

(8) Special reactions. As the preceding.

Mineral. Antimony blende

Formula. [,,,Sb]^{2} + [...Sb].

Behavior

(1) in gla.s.s-bulb. Fuses easily, gives off first SbO^{3} and afterwards an orange colored sublimate.

Strongly heated, is decomposed and gives a black sublimate, which becomes brown on cooling.

(2) in open tube. As the preceding.

(3) on charcoal. As the preceding.

(4) in forceps. --

(5) in borax. As native antimony.