Vermiculite Health, Safety and Environmental Aspects
Silica is a very abundant material in a variety of forms and accounts for approximately 20% of the earths crust with 95% being quartz. It is present in nearly all mining operations, and as an extremely common mineral has been the subject of many detailed studies, summarized in the Crystalline Silica Primer published by the US Bureau of Mines. Trace amounts of free silica .