Tancaite-(Ce) is a very rare molybdate mineral[2] with the formula FeCe(MoO4)3•3H2O. It was found in Punta de Su Seinargiu locality on Sardinia, Italy.[3][4] Red crystals of tancaite-(Ce) resemble modified cubes, but the mineral is trigonal (space group R-3).[2] The type locality of tancaite-(Ce) is also a place of discovery of other molybdate minerals, including thoriummolybdatesichnusaite and nuragheite.[5]