| 摘要 |
759,181. Electrodeposition of bright gold alloy. SEL-REX PRECIOUS METALS, Inc. Dec. 29, 1953 [April 1, 1953], No. 36038/53. Class 41. Bright gold alloy is deposited by electrolysis of a bath containing potassium gold cyanide, free potassium cyanide, and an amount of potassium silver cyanide less than that which would give a green tinge to the gold. Typically the bath comprises in one litre of water 90 grams of potassium cyanide, 12 grams of potassium gold cyanide containing 20.99 grams of gold per Troy ounce, and 0.16 grams potassium silver cyanide. The bath may also contain 3.5 grams of potassium nickel cyanide as a hardening agent and/or 8 grams of sodium thiosulphate as a brightening agent. The potassium cyanide and potassium silver cyanide may be dissolved in water first and added to a potassium gold cyanide solution. The deposited alloy consists of 99 per cent gold and 1 per cent silver. |
