Glass

Glass is chemical compounds which made from silica (SiO2)and other mixture（basic oxide or rare-earth element）. Its crystal structure is Noncrystalline .The various kinds of glass product we saw in the markets are usually used as the building materials ,industry instruments ,or household utensils.

But here what we mention is not the previous kind,we mean the gems-imitation glass .As gemstone imitation, it should contain the following specifications as the real gemstone it has:

Colors,transparency, refractive index,density together with other special optical effects.

Generelly speaking ,gemstone-imitation glass usually have the hardness of 5.5,and refractive index between 1.48to1.49, but the lead glass or the rare-earth glass with a refractive index measured above 1.70.

Gems-Imitation Glass and their Process procedure.
Different Transparent glass

1，Stained glass

Just add some certain coloring agents into the glass raw materials,for instanse:

2，Quartz Glass,  also refer to smelting quartz,this kind of glass is made of quartz leftover bits ,pieces (of industrial material) and quartz fragments.They need the procesing procedures such as purification，fusion，refrigeration,carving and polishing ,as per the last procedure, they use the tin oxide as their polishing compound.This gemstone-imitation glass is mainly used to imitated the white quartz products,such as engrave parts，necklace,crystall ball as well as other crafts.

3，Aquamarine glass，this kind of glass is made of colorless aquamarine pieces or pieces with impurity.The procedures are as the same as the quartz glass.They need the procesing procedures such as purification，fusion，refrigeration,carving and polishing ,as per the last procedure, they use the tin oxide as their polishing compound.This kind of glass is used to imitated the Emerald gems.

4，Lead glass, this kind of glass is made of ordenary glass and add some lead oxide mineral materials. This product have better luster ,hardness,as well as refractive index ,because its high percentage of lead element,usually up to 24 percent.So the white lead glass is used to imitated the diamond ,but its fatal weakness are low hardness and frangibility

 Here we’d like to mention the famous Glass producer Swarovki.Their glass prodcut,with lead content up to 30%, is once regard as the Diamond of Austria,and sells very well since 1990s and other products can't be compared with.Their glass is used to imitate diamond and other crystal crafts.

5，Rare-earth glass：This glass is made of ordinary glass with rare-earth element addition as the coloring agent.This kind of glass features in high refractive index,good luster,brilliant colors，and it can be used to imitated almost any type gemstones.

Subtransparent and Non-transparent Glass

  Cat’s eyes glass, Glass emerald(also refer to Malasia jade),Glass opal, Lapis Lazuli imitation ,Glass pearl,Aventurine(Also refer to aventurine glass).

How to identify glass imitations.