(H₃O)K(UO₂)SiO₄

This sample of boltwoodite is displayed in the Smithsonian Museum of Natural History. Boltwoodite is a silicate mineral that contains uranium . It has the composition (H₃O)K(UO₂)SiO₄. The sample at left is about 4 cm across and is from Roessing mine, Namibia.