Nahcolite

 ( Carbonate Minerals ) 

Nahcolite is a soft, colourless or white carbonate mineral with the composition of sodium bicarbonate (SodiumHydrogenCarbonOxygen₃) also called thermokalite. It crystallizes in the monoclinic system.

Nahcolite was first described in 1928 for an occurrence in a Lava tube at Mount Vesuvius, Italy. Nahcolite on Mindat.org Its name refers to the elements which compose it: Na, H, C, and O.Richard V. Gaines, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason, and Abraham Rosenzweig: Dana's new mineralogy, John Wiley & Sons, 1997 It occurs as a hot spring and saline lake precipitate or efflorescence; in differentiated alkalic ; in fluid inclusions as a daughter mineral phase and in evaporite deposits. Nahcolite data on Webmineral

It occurs in association with trona, thermonatrite, thenardite, halite, gaylussite, burkeite, northupite and borax. It has been reported in a Roman conduit at Stufe de Nerone, Campi Flegrei, near Naples; in the United States from Searles Lake, San Bernardino County, California; in the Green River Formation, Colorado and Utah; in the Tincalayu deposit, Salar del Hombre Muerto, Salta Province, Argentina; on Mt. Alluaiv, Lovozero Massif and Khibiny Massif, Kola Peninsula, Russia; and around Mount Erebus, Victoria Land, Antarctica.