Thermonatrite is a naturally occurring evaporite mineral form of sodium carbonate, Na2CO3·H2O.Handbook of MineralogyMindat data
It was first described in 1845.Webmineral data Its name is from the Greek θερμός thermos, "heat", plus natron, because it may be a dehydration product of natron.
Typical occurrence is in dry saline lake beds and as soil encrustations. It has been reported from volcanic fumaroles and in association with carbonatite-related veins. Common associated minerals include trona, natron and halite.
See also Nahcolite Natron Niter Potassium nitrate Shortite Soda (disambiguation) Sodium sesquicarbonate Trona
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