Heat the objects to about 608° F., whereby the powder is melted and acquires the consistency of a thin paste. In case of too high a temperature decomposition will set in.
To Find The Number Of Carats.
Acid Test For Gold.
Imitation Diamonds.
II.—Washed white sand, 100 parts (by weight): minium, 35 parts; calcined potash, 25 parts; calcined borax, 20 parts; nitrate of potash (crystals), 10 parts; peroxide of manganese, 5 parts. The sand must be washed as above stated.
Diamantine.
To Refine Board Sweepings.
Restoration Of The Color Of Turquoises.
Colorings For Jewelers’ Work.
II.—One hundred parts of calcium bromide and 2 parts of bromium. The objects are allowed to remain in this solution (which must be also constantly stirred) for from 2 to 3 minutes, then washed in a solution of sodium hyposulphite, after which they must be rinsed in clean water.