Mineral.  White arsenic

Formula.  AsO^{3}.

Behavior

  (1) in glass-bulb.  Sublimes without fusion and re-condenses in
                         white crystals.

  (2) in open tube. —­

  (3) on charcoal.  Sublimes and is partly recondensed on
                         charcoal forming a white incrustation.

  (4) in forceps.  Colors the flame blue.

  (5) in borax. —­

  (6) in mic. salt. —­

  (7) with carb. soda. —­

  (8) Special reactions.  Heated with charcoal in a glass-tube sealed
                         at one end, is reduced and metallic arsenic
                         sublimes.

* * * * *

MERCURY.

* * * * *

Mineral.  Native mercury

Formula.  Hg.

Behavior

  (1) in glass-bulb.  Volatilizes with little or no residue and
                         recondenses in neck of bulb.

  (2) in open tube. —­

  (3) on charcoal.  Is volatilized.

  (4) in forceps. —­

  (5) in borax. —­

  (6) in mic. salt. —­

  (7) with carb. soda. —­

  (8) Special reactions. —­

* * * * *

Mineral.  Cinnabar

Formula.  HgS.

Behavior

  (1) in glass-bulb.  Volatilizes sometimes leaving a slight
                         earthy residue, and re-condenses as a black
                         sulphide.

  (2) in open tube.  If gently heated is decomposed into metallic
                         mercury, which volatilizes and recondenses
                         in the upper part of the tube, and SO^{2},
                         which passes off as is easily recognized by
                         its odor and bleaching properties.

  (3) on charcoal.  Is volatilized, generally leaving a small
                         earthy residue.

  (4) in forceps. —­

  (5) in borax. —­

  (6) in mic. salt. —­

  (7) with carb. soda.  With carbonate of soda and cyanide of
                         potassium is decomposed and metallic mercury
                         volatilized.

  (8) Special reactions.  When in the preceding experiment the mercury
                         has been entirely dissipated, the alkaline
                         residue laid on silver gives a sulphur
                         reaction.

* * * * *

Mineral.  Native amalgam

Formula.  AgHg^{2}.