Quartz Producing Expert SiO2:99.9999% Certi:ISO9001,ISO14001,OHSA18001 silica powder,high purity silica powder,quartz sand The product is widely used: halogen lamps, ... crucible, crystal powder, silicon powder, fused quartz,silica powder,high purity silica powder,quartz sand Tolerance Dimensional Tolerance Diameter Range Range of OD ... 0% 2.5mm 6.00-15.00mm ± 1.25% ± 8% 10% 1.5% 2.5mm 15.00-20.00mm ± ...