The compound stone definition is also called composite stone, which is a gemstone made of two different materials. The type of doublet stone is classified according to the nature of the material used in the bonding. The types of double stones are garnet and glass double stone, emerald substitute, opal stone substitute, star sapphire substitute, diamond substitute, and other various imitation gemstones. Polyethylene Isolation Gown,Yellow Isolation Gown,Reusable Protective Gowns,3 Level Isolation Gown Jiangsu Yijin Import and Export Trade Co., Ltd , https://www.dailysafecare.com