Patent · US Expired

Sterling silver alloy compositions of exceptional and reversible hardness, and enhanced tarnish resistance

US7198683B2 · kind B2 · utility

7Cited by
10References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 26, 2004
Grant dateApr 3, 2007
Priority date
Expiry dateJul 23, 2025

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC22F1/14
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A sterling silver alloy composition of exceptional and reversible hardness and enhanced tarnish resistance, consists essentially of the following parts by weight: at least about 92.5% silver; about 4.4% to about 5.25% copper; about 0% to about 1.0% zinc; about 0.85% tin; about 0.05% to about 0.3% lithium; about 0.05% to about 0.5% silicon; about 0% to about 1.2% germanium; and about 0% to about 0.02% boron.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.