The chemical formula of talc is Mg3•Si4O10(OH)2. Talc is a hydrated magnesium mineral with flaky, tabular, tubular and granulate shapes, and white, light green, pink and waxy colors. Talc is acid and alkali resistant, corrosion resistant and heat resistant, with high chemical inertness. It is a poor conductor of heat and electricity. Talc is the softest mineral that has been known. When scratched with fingernail, scratch marks will be left on Talc.