Atomic_number_90WordNet Explorer

a soft silvery-white tetravalent radioactive metallic element; isotope 232 is used as a power source in nuclear reactors; occurs in thorite and in monazite sands

any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.

a reddish-brown mineral containing rare earth metals; an important source of thorium and cerium

a radioactive mineral consisting of thorium silicate; it is a source of thorium that is found in coarse granite

radioactive isotope of thorium with mass number 228