Through the use of hardness and abrasion testing, an attempt was made to determine the optimum time and temperature conditions for hardening selected commercially available gold and silver alloys. The test was performed with gold and silver alloys in a cold-worked, fully annealed state and precipitation-hardened alloys. The test procedures were then used to establish the optimum times and temperatures for precipitation hardening of gold and silver alloys. It is hoped that by developing simple, in-shop procedures for assessing hardness and showing the effectiveness of hardening, jewelers will embrace the practice of hardening gold and silver alloys by thermal treatments and improve the quality of handcrafted jewelry.

Author(s): Gary Dawson, Stewart Grice, Dr. Andrew Nyce