Grey gold ring 750 (18 kt) in the Art Deco style set with orange sapphire, rubies and diamonds
Gemmological certificate

Sapphire : Sapphire is a gemstone of the family of the mineral corundum. The most famous color for Sapphire is blue, but trace amounts of other elements can give yellow, purple, orange, or greenish sapphires. In the case of chromium impurities in corundum it would be called a called a Ruby. Sapphires are found in Sri Lanka, Myanmar or Australia.
Grey gold : Grey gold is obtained by adding silver, manganese and copper in specific ratios to the gold alloy.
Gold : Because of the softness of pure gold, it is alloyed with silver, copper or palladium. The proportion of these other metals give yellow, white gold. Without precision, the gold used in jewelry is 18 K, corresponding to 75% pure gold.
Size : Ring size. It is often possible to reduce or enlarge the size of the ring.