Physics

Samarium Definition Samarium is a silvery-white metallic element of the lanthanide series that exists in several forms and has seven naturally occurring isotopes. Its atomic…

Lutetium Definition Lutetium is a silvery-white metallic element of the lanthanide series that is used in nuclear technology. It is the last element in the…

Euxenite Definition Euxenite is a rare brownish-black mineral containing erbium, cerium, uranium, columbium, and yttrium. Titanium replaces niobium–tantalum in the molecular structure to form the…

Ytterbium Definition Ytterbium is a soft, silvery-white metallic element of the lanthanide series that occurs as seven stable isotopes with symbol Yb. Its atomic number…

Praseodymium Definition Praseodymium is a soft, malleable, silvery metallic element of the lanthanide series that develops a green tarnish in air. It is the third…

Cerium Definition Cerium is a shiny, gray metallic element of the lanthanide series. It is ductile and malleable and is used in electronic components, alloys,…

Aragonite Definition Aragonite is a usually white, yellowish, or pink orthorhombic mineral that can occur in many different colors. It is a polymorph of calcite,…

Crocoite Definition Crocoite is a rare orange secondary mineral consisting of lead chromate in monoclinic crystalline form. It’s mineral consisting of lead chromate, PbCrO4, that…

Calcite Definition Calcite is a usually white, clear, pale-yellow or blue orthorhombic mineral. Calcite occurs in many different forms and is the main component of…

Holmium Definition Holmium is a soft, silvery, malleable metallic element of the lanthanide series. Its compounds are highly magnetic. Its atomic number 67; atomic weight…

Lanthanum Definition Lanthanum is a soft, malleable, silvery-white metallic element of the lanthanide series. It is the eponym of the lanthanide series, a group of…

Yttrium Definition Yttrium is a silvery metallic element found in the same ores as elements of the lanthanide series. It is almost always found in…