(2) in open tube. Fuses and gives off white fumes, part of which pass up the tube and part deposit immediately above the mineral. This latter if heated fuses to clear drops (TeO^{3}). The mineral residue becomes surrounded by fused [...Bi=], characterized by its yellow color. (3) on charcoal. Fuses to a metallic bead, colors the outer flame bluish green (Te and Se) and incrusts the charcoal around with the orange [...Bi=], beyond which is a white incrustation partly consisting of [...Te]. (4) in forceps. -- (5) in borax. The yellow oxide obtained upon charcoal gives the bismuth reaction, and the white incrustation of bismuth and telluric acid. (6) in mic. salt. As in borax. (7) with carb. soda. In the reducing flame yields a bead of metallic bismuth, part of which is part of the tellurium volatilized and incrusts the charcoal around. (8) Special reactions. The fused alkaline mass gives the sulphur reaction on silver. Also gives the tellurium reaction with charcoal and carbonate of soda. * * * * * LEAD. * * * * * Mineral. Galena Formula. PbS. Behavior (1) in glass-bulb. Generally decrepitates and gives off a small quantity of sulphur. (2) in open tube. Gives off SO^{2}, and when strongly heated, a white sublimate of [.Pb], [.S]. (3) on charcoal. Fuses and is reduced affording a bead of metallic lead, and forming an incrustation of PbO on the charcoal. Colors the outer flame blue. (4) in forceps. -- (5) in borax. The oxide formed upon charcoal gives the lead reaction. (6) in mic. salt. As in borax. (7) with carb. soda. As alone on charcoal. The fused alkali gives a sulphur reaction on silver. (8) Special reactions. -- * * * * * Mineral. Clausthalite Formula. PbSe. Behavior (1) in glass-bulb. Decrepitates slightly. (2) in open tube. Forms a sublimate of selenium, which is grey when thickly deposited, and red when thin.