A group of non-silicate minerals in which the WO4 radical is in combination with a number of metal cations. Important examples include wolframite ((Fe,Mn)WO4) and scheelite (CaWO4). Molybdenum may substitute for tungsten to give related minerals, e.g. the molybdates powellite (CaMoO4) and wulfenite (PbMoO4).