IRON.
Mineral. Iron pyrites
Formula. FeS^{2}.
Behavior
(1) in gla.s.s-bulb. Gives a considerable yellow sublimate of sulphur, and sometimes sulphide of a.r.s.enic. Also HS.
(2) in open tube. Sulphurous acid and sometimes a.r.s.enious acid are evolved.
(3) on charcoal. Gives off some sulphur, which burns with a blue flame. Residue fuses to a magnetic bead.
(4) in forceps. --
(5) in borax. The roasted mineral gives a strong iron reaction.
(6) in mic. salt. As in borax.
(7) with carb. soda. Fuses to a black ma.s.s, which spreads out on charcoal and gives the sulphur reaction on silver.
(8) Special reactions. --
Mineral. Magnetic pyrites
Formula.
[,Fe]^{5}[,,,Fe=].
Behavior
(1) in gla.s.s-bulb. --
(2) in open tube. Evolves sulphurous acid.
(3) on charcoal. Fuses to a magnetic bead black on the surface, and with a yellow shining fracture.
(4) in forceps. --
(5) in borax. As iron pyrites.
(6) in mic. salt. As in borax.
(7) with carb. soda. As iron pyrites.
(8) Special reactions. --
Mineral. Mispickel
Formula. FeAs + FeS^{2}.
Behavior
(1) in gla.s.s-bulb. A red sublimate of a.s.s^{2} is first formed and then a black sublimate of metallic a.r.s.enic.
(2) in open tube. Sulphurous and a.r.s.enious acids are evolved, the latter forming a white sublimate.
(3) on charcoal. Gives off much a.r.s.enic forming a white incrustation and fuses to a magnetic globule.
(4) in forceps. --
(5) in borax. As iron pyrites.
(6) in mic. salt. As in borax.
(7) with carb. soda. As iron pyrites.
(8) Special reactions. --
Mineral. Magnetic iron ore
Formula. Fe^{3}O^{4}
Behavior
(1) in gla.s.s-bulb. --
(2) in open tube. --
(3) on charcoal. --
(4) in forceps. In the blue flame, fuses on edges and remains magnetic.
(5) in borax. Gives the iron reaction.
(6) in mic. salt. As in borax.
(7) with carb. soda. --
(8) Special reactions. --