The structure of quartz, mica, and asbestos have the common basic unit of:
Asbestos [Ca Mg3O (Si4O11)] which is a type of amphibole has a general structure as:
Different forms of silica such as quartz, tridymite and cristobalite are as follows: Quartz 870∘C⟶ Tridymite 1470∘C⇌ Cristobalite
(SiO2) (SiO2) (SiO2)
The structure possessed in them is: