Difference Between Silica and Quartz | Compare the ...
Feb 23, 2012· Silica. Silicon exists as its oxide in nature. Silica is the most common silicon oxide, with the molecular formula SiO 2 (silicon dioxide). Silica is an abundant mineral on the earth crust, and it is in sand, quartz and many other minerals. Some minerals have pure silica but, in some, silica are mixed with other elements.