Trona, hydrated sodium bicarbonate carbonate (Na3HCO3CO32H2O), is an 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.

Trona is found at Owens Lake and Searles Lake, California; Green River Formation, Utah; and the Nile Valley in Egypt. The trona near Green River, Wyoming is the largest known deposit in the world and lies in deep veins at 900 and 1600 feet below ground level. Trona has also been mined at Lake Magadi in the Rift Valley in Kenya for nearly 100 years, and occurs in 'salt' pans in the Etosha National Park in Namibia.

The word "trona" comes to English by way of either Swedish (trona) or Spanish (trona), with both possible sources having the same meaning as in English. Both of these derive from the Arabic tr?n which in turn derives from the Arabic natron, and Hebrew nun, tet, resh, nun pronounced natrun,which comes from the ancient Greek nitron, derived ultimately from the ancient Egyptian ntry (or nitry).