(3) on charcoal.  The powdered mineral fuses fuses to a black
                         shining mass, which in the reducing flame
                         affords a metallic bead.  Incrusts the charcoal
                         first with a white film of PbCl and afterwards
                         with PbO.

  (4) in forceps.  As pyromorphite.

  (5) in borax.  Dissolves readily to a clear glass, which, in
                         the oxidizing flame, is yellow, while hot, and
                         colorless when cold.  In reducing flame becomes
                         opaque, and on cooling green.

  (6) in mic. salt.  In oxidizing flame is yellow while hot, becoming
                         paler on cooling.  In reducing flame brown while
                         warm, and emerald green when cold.

  (7) with carb. soda.  On platinum wire fuses to a yellow bead, which
                         is crystalline on cooling.  On charcoal yields a
                         button of metallic lead.

  (8) Special reactions.  With microcosmic salt and CuO, gives the chlorine
                         reaction.  If fused in a platinum spoon with from
                         3 to 4 times its volume of [.K],[...S]^{2} it
                         forms a fluid yellow mass having an orange color
                         when cold.

* * * * *

Mineral.  Crocoisite

Formula. [.Pb][...Cr].

Behavior

  (1) in glass-bulb.  Decrepitates violently and assumes a dark color.

  (2) in open tube. —­

  (3) on charcoal.  Fuses and detonates yielding Cr^{2}O^{3} and
                         metallic lead, and forming an incrustation of
                         PbO on the charcoal.

  (4) in forceps.  As pyromorphite.

  (5) in borax.  Dissolves readily and colors the glass yellow
                         while warm, and green when cold. (See Chromium
                         reaction.)

  (6) in mic. salt.  As in borax.

  (7) with carb. soda.  On platinum foil gives a dark yellow mass, which
                         becomes paler on cooling.  On charcoal yields a
                         metallic button.

  (8) Special reactions.  Treated as above with [.K],[...S]^{2} forms a
                         violet colored mass, which on solidifying
                         becomes reddish and on cooling pale grey.

* * * * *

Mineral.  Molybdate of lead

Formula. [.Pb][...M].

Behavior

  (1) in glass-bulb.  As the preceding.

  (2) in open tube. —­