Sylvite

Sylvite is an economically important mineral and is extensively mined, though it is rarely represented in mineral collections as attractive specimens. It is the most significant form of potash, or potassium-bearing compounds, and has many industrial uses.

Sylvite is very similar to Halite, and is ismorphous with it, but it has a more bitter taste an greater solubility. It sometimes forms as a contrasting accessory mineral to deeply colored Halite specimens. Sylvite is named after named after François Sylvius de le Boe (1614-1672), a Dutch chemist and physician.

Sylvite was first discovered in very small crystals in the volcanic fumaroles of Mt. Vesuvius, Naples Province, Italy. Other important European localities include Muntanya de Sal (Salt Mountain), Cardona, Catalonia, Spain; and the Boulby Mine, Loftus, Yorkshive, England. In Germany, good Sylvite has been found at Wathlingen, Lower Saxony; Stassfurt, Saxony-Anhalt; and at the Hattorf Potash Works, Werra valley, Hesse.

In the U.S., the two most important deposits of Sylvite are the Carlsbad Potash District, Eddy Co., New Mexico; and Niland, near the Salton Sea, Imperial Co., California. Some of the world's largest deposits of Sylvite are in Canada in the province of Saskatchewan, especially at Esterhazy and Rocanville.