Talc

Talc
Magnesium silicate
The term talc refers both to the pure mineral and a wide variety of soft, talc-containing rocks that are mined and utilized for a variety of applications. Talc forms mica-like flakes. Talc is the softest mineral on the Mohs hardness scale at 1 and can be easily cut and crushed. Talc has perfect cleavage in one direction. This means that it breaks into thin sheets. As a result, it feels greasy to the touch (which is why talc is used as a lubricant).

Uses
Ground talc is used as an ingredient in ceramics, paper, paint, roofing, plastics, cosmetics, talcum and baby powders, and a variety of other assorted uses such as making rubber and plastics.
Element Type 1

SiO2 60-62 60-62 60-61 60-61 57-58 55-56 52-54
MgO 31-32.5 31-32.5 30-31 30-31 29-30 27-28 25-26
Al2O3 0.3-0.5 0.3-0.5 0.5-1.2 0.5-1.0 1.4-1.8 2-2. 2.8-3.2
Fe2O3 0.1-0.2 0.1-0.2 0.25-0.40 0.20-0.40 0.5-0.7 0.75-0.80 0.9-1
CaO 0.3-0.5 0.14-0.3 0.6-1.1 0.5-1.0 1.5-2.0 2.3-2.9 3.2-4.5
Na2O