Kaolinite
Kaolinite is a layered silicate clay mineral which forms from the chemical weathering of feldspar or other aluminum silicate minerals. It is usually white, with occasionally a red color impurity due to iron oxide, or blue or brown from other minerals. Kaolinite has a low shrink–swell capacity and a low cation-exchange capacity, making it ideal for many industrial applications.
Type
Mineral
Mineral Classification
Phyllosilicates
Chemical Formula
Al2Si2O5(OH)4
Streak
White
Mohs Hardness
2–2.5
Crystal System
Triclinic
Color
White, sometimes red, blue or brown tints from impurities
Luster
Pearly to dull earthy
Fracture
Irregular/uneven, conchoidal, sub-conchoidal, micaceous
Description
Kaolinite is a layered silicate clay mineral which forms from the chemical weathering of feldspar or other aluminum silicate minerals. It is usually white, with occasionally a red color impurity due to iron oxide, or blue or brown from other minerals. Kaolinite has a low shrink–swell capacity and a low cation-exchange capacity, making it ideal for many industrial applications.
Uses
During 2013, 48% of Kaolin was used in paper production, and 52% was used for ceramics, light bulbs, paint, rubber, adhesives, smoking pipes, white wash in masonry, absorbents, and in soap. Within organic farming kaolinite is used as a form of pest control. It is an active ingredient within medicines for diarrhea, nausea, and other digestive issues.
