Mineralogy of talc
Talc is both natural mineral, and earth material, formed by this mineral. It is industrial finely granular raw materials, used in various industries primarily as a filler. Finally, talc is a cosmetic powder, the most popular application «for the man in the street».
Mineral talc is hydrous magnesium silicate with the following chemical formula:
Talc is the softest mineral (hardness 1 on the Mohs scale)
Specific density - 2.7-2.85 g/cm3
Reflection coefficient of 1.59-1.6
Talc has no odor, is practically insoluble in water and diluteâ solutions of acids and alkalis. It is neither explosive nor flammable.
Talc is close to some organic substances and is therefore an organophilic mineral. Organophilic properties of talc contribute to good crystallization of polypropylene, involvement of organic resins particles in paper manufacture and absorbability in cosmetic products.
The crystal breaker plate of talc is formed by a layer of magnesium oxide, framed by two layers of non-polar tetraerov of silica and oxygen. The outer surface of flakes contains neither hydroxyl groups nor active ions, resulting in high chemical stability and hydrophobicity of talc.
Three-layer crystals of talc, having a very strong internal tie among them are bound very weakly. This determines a lot of physical and mechanical properties of talc: softness, sliminess, slipperiness, adhesiveness, easy splitting and reducibleness.