“* 
NATIVE COPPER IODIDE AND OTHER MINERALS. 327 
Heated in closed tube; partly fuses, spreads up tube, dark 
brown when hot, reddish-brown when cold ; partly volatilized as 
beautiful violet fumes, condensing on cold part of tube as steel-grey 
acicular crystals, which are volatilized in violet fumes on heating, 
leaving a whitish skeleton residue. 
Heated in open tube partly fuses with dense violet fumes, con- 
densing on cool part of tube, having acid reaction, fused mass 
greenish-yellow, by further heating violet-black. 
Heated on charcoal in O.F.; effervesces with dense green flame, 
(similar to tellurium) coating charcoal near assay dirty red, sur- 
rounded by yellowish-green, passing over in outer part to bluish- 
white, with white border. This is consumed by continued blowing 
in O.F. or R.F. with dirty green flame in outer parts, changing 
to bluish-green nearer the assay piece, after which iridescent stains 
are left on the charcoal. 
On charcoal in R.F. alone, much the same as above. With 
soda, dense bluish fumes, with heavy white incrustation, leaving 
eventually a globule of copper* and magnetic specule. (The latter 
probably due to mechanical impurities). With borax or phosphor 
salt on platinum wire, gives copper reaction with green flame. 
Powder treated with cold HNO,, slightly soluble, solution 
brownish-oil green. Hot, gives deep red solution, from which 
violet fumes escape, condensing on cool part of tube, as translucent 
steel-grey acicular crystals, (which removed and dissolved in water 
gives blue solution with starch) similar crystals form in solution 
while cooling. These may again be dissipated by boiling, after 
which the clear solution gives with ammonia the reaction for 
copper, and a yellowish-white precipitate with silver nitrate. 
No precipitate with barium nitrate, slight colouration with 
ammonium molybdenum. This precipitate after washing, treated 
in bead of phosphor salt gives pure green flame colouration; after 
removal of precipitate the solution gives a blue colour with 
starch water. | 
* The globule of metal dissolved in HNO; gives copper reaction with 
ammonia, no precipitate with H,SO, or HCl. 
