(n.) A native double salt, consisting of a combination of neutral and acid sodium carbonate, Na2CO3.2HNaCO3.2H2O, occurring as a white crystalline fibrous deposit from certain soda brine springs and lakes; -- called also urao, and by the ancients nitrum.
TRONA
Meaning of TRONA in English
Webster's English dictionary. Английский словарь Webster. 2012