Abstract: Pottsite occurs in the oxide zone of a tungsten mine northwest of Potts, Lander County, Nevada, and is named for the locality. It occurs with scheelite, clinobisvanite, bismutite, and vanadinite. The colour is yellow, luster adamantine. D_obs. is 7.0, D_calc. 7.31. Uniax (-) ω = 2.49, ɛ = 2.37. Microprobe analysis gave PbO 32.4, Bi₂O₃ 34.0, V₂O₅ 26.6; H₂O by Penfield method 6.71% (total 99.71%), leading to HPbBi(VO₄)₂·2H₂O. Crystals are tetragonal 14₁22, a = 11.084, c = 12.634Å. Strongest powder diffraction lines are 4.618 (9), 4.168 (3), 3.210 (4), 3.062 (10), 2.476 (4), 2.252 (3).