High purity quartz, also known as HPQ, is a commercial form of silicon dioxide (SiO2) that contains an exceptionally low level of impurities. It is found in nature as rock crystal or crystal sand and must undergo an extensive purification process to achieve the stringent purity levels required for many modern industrial applications. https://articlescad.com/high-purity-quartz-an-essential-raw-material-328984.html