alloys of noble metals and nonferrous metals used in the manufacture of jewelry. The addition of specific components to an alloy makes it possible to alter the alloy’s mechanical properties (strength, hardness, elasticity, and resilience) and technical properties (flowability, casting shrinkage, malleability, weldability, and suitability for cutting), as well as the color of an alloy. In the USSR, gold alloys with fineness numbers of 958,750, 583, and 375 are used in the manufacture of jewelry (seeGOLD ALLOYS and FINENESS).
Silver and copper, among other metals, are added to gold alloys to alter the color from light yellow to reddish and to increase alloy strength, zinc and cadmium are added to significantly reduce the melting point and to increase flowability, and palladium and nickel are added to impart a light color, including white. Jewelry silver alloys contain copper as the only alloying component, which enhances the strength and hardness of an alloy.
The labeling system for jewelry alloys adopted in the USSR uses letters and numbers. The letters indicate the components within the alloy: Zl for gold (zoloto), Sr for silver (serebro), Pd for palladium (palladii), M for copper (med’), N for nickel (nikel). Ts for zinc (tsink), K for cadmium (kadmii), and O for tin (olovo). The numbers indicate the content of noble metals (in terms of fineness). Thus, the gold alloy ZlSrM 583–80 contains 58.3 percent gold, 8 percent silver, and the remainder copper, while the silver alloy SrM 875 consists of 87.5 percent silver and the remainder copper.
The alloys used in other countries for the manufacture of jewelry differ only slightly with respect to the noble metal content from those used in the USSR.
E. I. IVANOV