950 Hard Platinum Information Sheet

Hoover & Strong’s new platinum alloy was developed as a direct response to customers looking for a harder platinum alloy. The result is PTH, harder than the traditional 950 alloys without the need for heat treatment. For improved casting, PTH offers a wider temperature range between liquid and solid states enabling a better cavity fill. PTH has an annealed hardness of 180HV, 33% harder than 950 platinum-ruthenium and 64% harder than 900 platinum-iridium. This alloy improves rigidity and wear over traditional alloys, and is ideal for customers who want a stiffer alloy for prongs, pave applications and clasps, or for those who want their alloy to have increased resistance to deformation and impact. PTH has a high initial work hardening rate so that stones are easily set, but once the prong is bent into position, it stays there. PTH is ideal for all platinum jewelry manufacturing applications, whether investment casting or general fabrication, and retains the excellent white color and luster associated with 950 quality platinum alloys.

Recommended Uses: PTH can be used for all general fabrication techniques.