Nomenclature
CAS number: 1318-00-9
Hydrated magnesium-aluminum-iron silicate.
Description and references
Typical analysis of Montana vermiculite ore:
SiO2 38.64%, MgO 22.68%, Al2O3 14.94%,
Fe2O3 9.29%, K2O 7.84%, CaO 1.23%,
Cr2O3 0.29%, Mn3O4 0.11%,
Cl 0.28%.
Properties
Monoclinic crystals, pseudo-hexagonal characteristics.
Soft, resilient, glabrous feel. Dissolves in hot concd H2SO4. Has base exchange capacities. Sold as the ore or
in “expanded” form. The expanded grades can absorb large quantities
of liquids and remain free flowing. The ore is not sol in weak acids
or bases, but expanded grades may be attacked. Vermiculites should
be classed as montmorillonoids: Rustum Roy, Chem. Eng. News 32, 4842 (1954).Note
A food grade vermiculite is known as Verxite.Use
As catalyst; loose fill insulation, filler and packing
material.