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Kyanite is a typically blue aluminosilicate mineral, found in aluminium-rich metamorphic pegmatites and sedimentary rock. It is the high pressure polymorph of andalusite and sillimanite , and the presence of kyanite in metamorphic rocks generally indicates metamorphism deep in the Earth's crust .
It is Henry Goblot who explores the genesis of qanat for the first time. He argues in his book entitled “Qanats; a Technique for Obtaining Water” the ancient Iranians made use of the water that the miners wished to get rid of it, and founded a basic system named qanat or Kariz to supply the required water to their farm lands.
Andalusite, kyanite, and sillimanite are the principal aluminium silicate minerals. [2] [3] [4] The triple point of the three polymorphs is located at a temperature of 500 °C (932 °F) and a pressure of 0.4 GPa (58,000 psi). These three minerals are commonly used as index minerals in metamorphic rocks.
An example is provided by the aluminium silicate minerals, kyanite, andalusite, and sillimanite. All three have the identical composition, Al 2 SiO 5. Kyanite is stable at surface conditions. However, at atmospheric pressure, kyanite transforms to andalusite at a temperature of about 190 °C (374 °F).
Kaolinite (/ ˈ k eɪ. ə l ə ˌ n aɪ t,-l ɪ-/ KAY-ə-lə-nyte, -lih-; also called kaolin) [5] [6] [7] is a clay mineral, with the chemical composition Al 2 Si 2 O 5 4.It is a layered silicate mineral, with one tetrahedral sheet of silica (SiO 4) linked through oxygen atoms to one octahedral sheet of alumina (AlO 6).
Kainite (/ ˈ k aɪ n aɪ t / or / ˈ k eɪ n aɪ t /) [4] (KMg(SO 4)Cl·3H 2 O) is an evaporite mineral in the class of "Sulfates (selenates, etc.) with additional anions, with H 2 O" according to the Nickel–Strunz classification. It is a hydrated potassium-magnesium sulfate-chloride, naturally occurring in irregular granular masses or as ...
A few minerals such as calcite and kyanite have a hardness that depends significantly on direction. [9]: 254–255 Hardness can also be measured on an absolute scale using a sclerometer; compared to the absolute scale, the Mohs scale is nonlinear. [8]: 52 Tenacity refers to the way a mineral behaves, when it is broken, crushed, bent or torn.
Carnallite minerals are mineral sediments known as evaporites. Evaporites are concentrated by evaporation of seawater. The inflow of water must be below the evaporation or use levels. This creates a prolonged evaporation period. In controlled environment experiments, the halides form when 10%–20% of the original sample of water remains. [14]