Trona
Trona (trisodium hydrogendicarbonate dihydrate, also sodium sesquicarbonate dihydrate, Na2CO3•NaHCO3•2H2O) is a non-marine evaporite mineral. It is mined as the primary source of sodium carbonate in the United States, where it has replaced the Solvay process used in most of the rest of the world for sodium carbonate production. Etymology The word entered English by way of either Swedish () or Spanish (), with both possible sources having the same meaning as in English: the mineral natron from North Africa. Both the Spanish and Swedish terms derive from the Arabic trōn, which in turn derives from Arabic natron and Hebrew (natruna), which comes from ancient Greek (nitron), derived ultimately from ancient Egyptian ntry (or nitry'’). Natural deposits Trona is found at Owens Lake and Searles Lake, California; the Green River Formation of Wyoming and Utah; the Makgadikgadi Pans in Botswana and in the Nile Valley in Egypt. The trona near Green River, Wyoming, is the largest known deposit in the world and lies in layered evaporite deposits below ground, where the trona was deposited in a lake during the Paleogene Period. Trona has also been mined at Lake Magadi in the Kenyan Rift Valley for nearly 100 years. The northern part