Quartz is a hard, durable mineral composed primarily of silicon dioxide (SiO2). It is resistant to most acids, including hydrochloric acid (HCl), sulfuric acid (H2SO4), and nitric acid (HNO3). However, quartz can be dissolved by hydrofluoric acid (HF) to form silicon tetrafluoride (SiF4) gas. The reaction between quartz and hydrofluoric acid is:

SiO2(s) + 4HF(aq) -> SiF4(g) + 2H2O(l)

This reaction is used in the etching of glass and other quartz-containing materials.