タグアーカイブ: How does the national standard classify jewelry and jade?

中国の金メッキペンダント工場 国家基準は宝石と翡翠をどのように分類していますか?

In my country’s jewelry industry, the gems are classified according to their genesis types, and gems are divided into two categories: natural and artificial. Then it is further divided according to the composition and properties of gems. When categorizing jewelry and jade, taking into account the versatility and habit in the world, try to use […]