The rich gem resources in the world are mainly concentrated in Africa, アジア, America and Oceania. 1. Africa The African continent is rich in gem resources and is known as the “World Gem Warehouse”. It is rich in diamonds, ルビー, サファイア, golden emeralds, エメラルド, アクアマリン, アメジスト, peridot and turquoise, among which diamonds are the most […]
