(7) with carb. soda. Forms sulphide of sodium and oxide of iron. The former is absorbed into the charcoal, and if cut out and laid upon silver and moistened gives the S reaction. (8) Special reactions. If dissolved in water, and a strip of silver-foil be introduced into the solution, the metal remains untarnished. * * * * * Mineral. Vivianite Formula. [.Fe]^{3}[.....P] + 8[.H]. Behavior (1) in glass-bulb. Gives off water. (2) in open tube. -- (3) on charcoal. Froths up and then fuses to a grey metallic bead. (4) in forceps. As on charcoal. Singes flame green ([.....P]). (5) in borax. Gives the iron reaction. (6) in mic. salt. As in borax. (7) with carb. soda. In reducing flame becomes magnetic and fuses to a black saggy mass. (8) Special reactions. -- * * * * * Mineral. Iriphyline Formula. ([.Fe][.Mn][.Li])^{3}[.....P]. Behavior (1) in glass-bulb. Gives off water, having an alkaline reaction, and assumes a metallic lustre resembling graphite. (2) in open tube. -- (3) on charcoal. Fuses readily to a black magnetic bead with a metallic lustre. (4) in forceps. I. On platinum wire colors the flame crimson ([.Li]) and green ([.....P]), towards the point fuses to a black magnetic bead. (5) in borax. Gives the iron and manganese reactions. (6) in mic. salt. Gives the iron reaction which overpowers that of the manganese. (7) with carb. soda. Forms an infusible porous mass, which under the reducing flame becomes magnetic. (8) Special reactions. Gives the manganese reaction with nitre and carbonate of soda on platinum foil. * * * * * Mineral. Scorodite Formula. [...Fe=][.....As] + 4[.H]. Behavior (1) in glass-bulb. Evolves water. (2) in open tube. Gives off water and AsO^{3}. (3) on charcoal. Emits arsenical fume and in the reducing flame fuses to a magnetic mass having a metallic lustre. (4) in forceps. I. As on charcoal. Colors the outer flame blue. (5) in borax. The roasted mineral gives an iron reaction. (6) in mic. salt. As in borax. (7) with carb. soda. As alone on charcoal. (8) Special reactions. Gives the arsenic reactions. * * * * * Mineral. Cube ore