A System of Instruction in the Practical Use of the Blowpipe Part 28

(8) Special reactions. If the alumina residue obtained be moistened with cobalt solution and heated strongly, it a.s.sumes a beautiful blue color.

BARYTA AND STRONTIA.

Mineral. Heavy-spar

Formula. [.Ba][...S].

Behavior

(1) in gla.s.s-bulb. Sometimes decrepitates and gives off more or less water

(2) in open tube. --

(3) on charcoal. Fuses in the reducing flame.

(4) in forceps. Fuses with difficulty on edges. Colors the outer flame green. In reducing flame forms BaS, which fuses readily.

(5) in borax. Gives the baryta-reaction.

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

(7) with carb. soda. Fuses to a clear bead; then spreads out and is absorbed into the charcoal. The fused ma.s.s laid on silver gives the S-reaction.

(8) Special reactions. If fused with pota.s.sa on platinum, gives the SO^{3}-reaction.

Mineral. Celestine

Formula. [.Sr][...S].

Behavior

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

(2) in open tube. --

(3) on charcoal. Fuses to a milk-white bead.

(4) in forceps. Colors the flame crimson.

(5) in borax. Gives the strontia-reaction.

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

(7) with carb. soda. Similar to the preceding.

(8) Special reactions. Similar to the preceding.

Mineral. Witherite

Formula. [.Ba][..C].

Behavior

(1) in gla.s.s-bulb. Decrepitates more or less and evolves Water.

(2) in open tube. --

(3) on charcoal. Fuses, effervesces, and is partially absorbed by the charcoal.

(4) in forceps. Colors the outer flame intensely green.

(5) in borax. Dissolves with effervescence and gives the baryta-reaction.

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

(7) with carb. soda. Fuses to a clear bead; then spreads out and pa.s.ses into the charcoal.

(8) Special reactions. In dilute HCl dissolves with much effervescence.

Mineral. Strontianite

Formula. [.Sr][..C].

Behavior

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

(2) in open tube. --

(3) on charcoal. As in the forceps.

(4) in forceps. Exfoliates and becomes arborescent. The filaments glow brilliantly and fuse on the point. Colors the flame brilliantly crimson.

(5) in borax. Resembles the preceding.

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

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