1886

Dysprosium

• After Per Teodor Cleve
• separated holmium and thulium from erbium oxide,
• Paul-Émile Lecoq de Boisbaudran
• separated dysprosium oxide from holmium oxide
• by dissolving the holmium oxide in acid
• and precipitating the solution with ammonia.

Atomic number 66

• Dysprosium is never free in nature.
• Seven stable isotypes are mixed in many minerals.
• The “D” in the name of the magnetostrictive alloy Terfenol-D
• stands for dysprosium.
• Neodymium–iron–boron magnets can have a little dysprosium
• to raise their resistance to corrosion and demagnetization.
• High-intensity metal-halide lamps
• may contain dysprosium halides.
• Adiabatic demagnetization refrigerators
• use paramagnetic crystal salts of dysprosium.

Hard to obtain

• Lecoq named the new element dysprosium,
• meaning “hard to obtain” in Greek,
• because it had repeated his chemical procedure
• more than thirty times
• before any disprosium appeared.