Material specification: 18ct Gold
Stem thickness: 0.8mm
Stone: 1.2pt brilliant (56 facet) Diamond
18 ct gold is 75% gold and the rest is silver and copper. 14 ct gold is 58.5% gold and the rest silver and copper. There is no nickel alloyed, which many people are allergic to, but of course you can be allergic to other metals like silver and copper.