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

  (5) in borax.  Gives the copper reactions.

  (6) in mic. salt.  As with borax.  The silica remains
                         undissolved.

  (7) with carb. soda.  With a small quantity of carbonate of soda
                         fuses to a bead, which on cooling is opaque
                         and has a red fracture.  With more alkali
                         forms a slag, containing little beads of
                         reduced copper.

  (8) Special reactions. —­

* * * * *

Mineral.  Malachite

Formula. [.Cu]^{2}[..C] + [.H].

Behavior

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

  (2) in open tube. —­

  (3) on charcoal.  Fuses to a bead with a strong flame is
                         reduced to metallic copper.

  (4) in forceps.  Fuses and colors the outer flame brilliantly
                         green.

  (5) in borax.  Gives the copper reaction.

  (6) in mic. salt.  As with borax.

  (7) with carb. soda.  Yields metallic copper.

  (8) Special reactions.  Dissolves in HCl with much effervescence.

* * * * *

Mineral.  Blue vitriol

Formula. [.Cu][...S] + 5[.H].

Behavior

  (1) in glass-bulb.  Intumesces, gives off water and becomes
                         white.

  (2) in open tube.  Strongly heated is decomposed, given off
                         SO^{2} and being converted into CuO.

  (3) on charcoal.  As in the glass-bulb.  Then fuses, coloring
                         the outer flame green, and is reduced to
                         metallic copper and [,Cu=].

  (4) in forceps.  Fuses and colors the outer flame blue.

  (5) in borax.  The roasted mineral gives copper reaction.

  (6) in mic. salt.  As in borax.

  (7) with carb. soda.  Yields metallic copper.  The alkaline mass
                         laid on silver gives S reaction.

  (8) Special reactions.  Gives the sulphuric acid reaction.

* * * * *

Mineral.  Libethenite

Formula.                 [.Cu]^{4}[.....P] + 2[.H].

Behavior

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

  (2) in open tube. —­

  (3) on charcoal.  Gradually heated, turns black and fuses to a
                         bead, having a core of metallic copper.

  (4) in forceps.  Fuses but does not color the flame
                         distinctly.  On cooling is black and
                         crystalline.