Min. [Native name. So F. urao.] = TRONA.
1839. Ure, Dict. Arts, 1263. Urao, is the native name of a sesquicarbonate of soda found at the bottom of certain lakes in Mexico.
1863. Watts’ Dict. Chem., I. 796. Tetrasodic Carbonate or Sesquicarbonate of Sodium … occurs … as urao at the bottom of a lake in Maracaibo, South America.
1889. Amer. Nat., XXIII. 814. The composition of urao, a mineral … from Venezuela.
