... .Ceramic products and jewelry tools Yihui castingCeramic ring chooses melted quartz as raw material, is mainly applied in the smelting of ... , good high temperature resistance and thermal stability. Its main component SiO2 >98%, impurity(K2O,Na2O,Fe2O3)<0.2%. It has high ... the pressure under normal temperature>70MPa . Ceramic ring,jewelry tools,Quartz products,ceramic gasket,ceramic loop