(5) in borax.  If the bead obtained on charcoal be fused on
                         that support in the reducing flame with borax, a
                         slight iron reaction is obtained, and after a
                         time a copper reaction.

  (6) in mic. salt.  As with borax.

  (7) with carb. soda.  Yields a bead of metallic copper and lead and
                         incrusts the charcoal with [...Sb] and [.Pb]. 
                         The alkaline mass laid on silver and moistened
                         gives the sulphur reaction.

  (8) Special reactions. —­

* * * * *

Mineral.  Red oxide of copper

Formula.  Cu^{2}O

Behavior

  (1) in glass-bulb. —­

  (2) in open tube.  Is converted into the black oxide CuO.

  (3) on charcoal.  In the reducing flame is reduced, forming a
                         bead of metallic copper.

  (4) in forceps.  Fuses and colors the the flame emerald
                         green, or if previously moistened with HCl,
                         blue.

  (5) in borax.  Gives the copper reaction.

  (6) in mic. salt.  As with borax.

  (7) with carb. soda.  Is reduced to a bead of metallic copper.

  (8) Special reactions. —­

* * * * *

Mineral.  Atacamite

Formula.  CuCl + 3[.Cu] + 6[.H].

Behavior

  (1) in glass-bulb.  Gives off much water, having an acid
                         reaction, on test paper, and forms a light
                         grey sublimate of CuCl.

  (2) in open tube. —­

  (3) on charcoal.  Fuses, colors the flame blue, forms a brown
                         and a pale grey incrustation on the
                         charcoal, and is reduced to metallic copper,
                         leaving a small quantity of slag.

  (4) in forceps.  Fuses and colors the outer flame intensely
                         blue and green towards the point.

  (5) in borax.  Gives the copper reactions.

  (6) in mic. salt.  As with borax.

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

  (8) Special reactions. —­

* * * * *

Mineral.  Dioptase

Formula. [.Cu]^{3}[...Si]^{2} + 3[.H].

Behavior

  (1) in glass-bulb.  Gives off water and turns black.

  (2) in open tube. —­

  (3) on charcoal.  In the oxidizing flame becomes black.  In the
                         reducing flame red.