Quartz Sand or Quartz Powder is manufactured by crushing crystalline quartz lumps to various sizes and is also known as white silica sand. Quartz Sand has very high silica content as compared to river sand and has negligible or no natural impurities. Quartz Sand is highly resistant to both mechanical and chemical weathering and makes an excellent filter media. When quartz lumps are grounded to the size of 2-3 mm stones, they are colloquially known as silex. Quartz sand has varied uses, some of them listed below.