Potash

chemical compound

chemical compound

Sylvite, or sylvine, is potassium chloride (KCl) in natural mineral form. It forms crystals in the isometric system very similar to normal rock salt, halite (NaCl). The two are, in fact, isomorphous. Sylvite is colorless to white with shades of yellow and red due to inclusions. It has a Mohs hardness of 2.5 and a specific gravity of 1.99. It has a refractive index of 1.4903. Sylvite has a salty taste with a distinct bitterness.

Carnallite (also carnalite) is an evaporite mineral, a hydrated potassium magnesium chloride with formula KCl.MgCl2·6(H2O). It is variably colored yellow to white, reddish, and sometimes colorless or blue. It is usually massive to fibrous with rare pseudohexagonal orthorhombic crystals. The mineral is deliquescent (absorbs moisture from the surrounding air to the point of forming an aqueous solution) and specimens must be stored in an airtight container.

thumb|Polycrystalline potash, with a penny (United States coin)|U.S. penny for reference. (The coin is in diameter and copper in color.)

Kainite ( or ) (KMg(SO4)Cl·3H2O) is an evaporite mineral in the class of "Sulfates (selenates, etc.) with additional anions, with H2O" according to the Nickel–Strunz classification. It is a hydrated potassium-magnesium sulfate-chloride, naturally occurring in irregular granular masses or as crystalline coatings in cavities or fissures. This mineral is dull and soft, and is colored white, yellowish, grey, reddish, or blue to violet. Its name is derived from Greek [kainos] ("(hitherto) unknown"), as it was the first mineral discovered that contained both sulfate and chloride as anions. Kainite f

Niter or nitre is the mineral form of potassium nitrate, KNO3. It is a soft, white, highly soluble mineral found primarily in arid climates or cave deposits.

Polyhalite is an evaporite mineral, a hydrated sulfate of potassium, calcium and magnesium with formula: . Polyhalite crystallizes in the triclinic system, although crystals are very rare. The normal habit is massive to fibrous. It is typically colorless, white to gray, although it may be brick red due to iron oxide inclusions. It has a Mohs hardness of 3.5 and a specific gravity of 2.8. It is used as a valuable fertilizer.

thumb|Sylvinite from Perm Krai, Russia thumb|Close-up view of sylvinite from Perm, Russia Sylvinite is a sedimentary rock made of a mechanical mixture of the minerals sylvite (KCl, or potassium chloride) and halite (NaCl, or sodium chloride). Sylvinite is the most important source for the production of potash in North America, Russia and the UK. Most Canadian operations mine sylvinite with proportions of approximately 31% KCl and 66% NaCl with the balance being insoluble clays, anhydrite and in some locations carnallite. Other deposits of sylvinite are located in Belarus, Brazil, France, Germa

Israeli potash plant on the Dead Sea coast