Lanthanide Series

A soft, ductile, silvery-white metal that tarnishes slowly when exposed to air. It is the first and the prototype of the lanthanide series, a group of 15 similar elements between lanthanum and lutetium in the periodic table. It has no biological role in humans but is essential to some bacteria.

A soft, ductile, and silvery-white metal that tarnishes when exposed to air. It is the second element in the lanthanide series, and while it often shows the oxidation state of +3 characteristic of the series, it also has a stable +4 state that does not oxidize water. Cerium dioxide is employed in the optics industry for the fine polishing of glass.

A soft, silvery, malleable and ductile metal that belongs to the rare-earth metals. It has the atomic number 59 and is the third member of the lanthanide series. Praseodymium has magnetic, electrical, chemical, and optical properties. It is too reactive to be found in native form, and pure praseodymium metal slowly develops a green oxide coating when exposed to air.

A rare-earth metal with the symbol Nd and atomic number 60. It is one of the most complex and reactive of the lanthanides, and has a silvery white appearance. It is used in magnets, alloys, and ceramics for various applications.

A radioactive lanthanide element with the symbol Pm and atomic number 61. It is one of the rarest and most expensive elements in the periodic table, with only about 500–600 grams naturally occurring in Earth’s crust at any given time. It is produced by the decay of uranium or europium, and has one stable isotope (147 Pm) with applications in luminous paint, atomic batteries and thickness-measurement devices.

A silvery metal with the symbol Sm and atomic number 62. It is a member of the lanthanide series and has the oxidation state +3. It is used in alloys, ceramics, and magnets.

A silvery-white metal of the lanthanide series that reacts readily with air to form a dark oxide coating. It is the most chemically reactive, least dense, and softest of the lanthanide elements. It is one of the rarest of the rare-earth elements on Earth and has no significant biological role.

A silvery-white metal with the symbol Gd and atomic number 64. It is a rare-earth element that reacts with oxygen or moisture to form a black coating. It is ferromagnetic below 20 °C and paramagnetic above it. It is found in nature only in an oxidized form and has impurities of other rare-earths.

A silvery-white, rare earth metal that is malleable and ductile. It is the ninth member of the lanthanide series and has the symbol Tb. It is used to dope materials, stabilize fuel cells and make alloys.

A rare-earth metal with the symbol Dy and atomic number 66. It is a metal with a metallic silver luster and a high thermal neutron absorption cross-section. Dysprosium has seven isotopes, the most abundant of which is 164 Dy. It is used for its high thermal neutron absorption cross-section in nuclear reactors and its high magnetic susceptibility in data-storage applications.

A silvery, soft, and malleable metal that belongs to the rare-earth metals. It has the atomic number 67 and is the eleventh member of the lanthanide series. Holmium has magnetic, electrical, chemical, and optical properties. It is too reactive to be found in native form, and pure holmium metal slowly develops a yellowish oxide coating when exposed to air.

A rare-earth element with the symbol Er and atomic number 68. It is a silvery-white solid metal that can be used in optical amplification media for laser applications. It has optical fluorescent properties and is found in chemical combination with other elements.

A rare-earth metal with the symbol Tm and atomic number 69. It is the thirteenth and third-last element in the lanthanide series. Thulium is a silvery-gray metal that is fairly soft and slowly tarnishes in air. It is used in portable X-ray machines, solid-state lasers, and high-temperature superconductors.

A rare-earth metal with the symbol Yb and atomic number 70. It is a soft, malleable silvery metal that will tarnish slightly when stored in air. It is used in lasers, alloys, and ceramics.

A rare-earth metal with the symbol Lu and atomic number 71. It is a silvery white metal that resists corrosion in dry air but not in moist air. It is the densest and the highest-melting rare-earth element and the last member of the lanthanide series.