QuartzProducingExpert ISO9001 ISO14001OHSAS18001 SiO2 99.9999% crystal powder ,silica powder,silicon powder Company: Donghai Shengda Quartz ... quartz sand,high purity quartz sand,quartz sand, quartz powder,crystal powder ,silica powder,silicon powder Our clear fused quartz ... controlled dimension and low OH, etc. They’re the best heat resisting material for lamps like: halogen lamps, mercury lamps, ...