Element Samarium, Sm, Lanthanide
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Samarium History
Samarium had been discovered as a result of persistent chemical-analytical and spectral research of didimia earth, extracted by Mosander from ceria earth. Several decades after Mosander's isolation of didimia earth form lanthana an element didymium was supposed to exist, however some chemists suspected that it was, in fact, a mixture of several elements. In 19th century the didimia earth was separated from the mineral samarskite that was first found in the in the Il'menskeye mountains, by the late 1870s, and it was from that source that the samarium-bearing didymium had originated.
The samarskite mineral was named after Vasili Samarsky-Bykhovets, the Chief of Staff (Colonel) of the Russian Corps of Mining Engineers in 1845-1861.
In 1878 Delafontaine reports about two blue spectrum lines; he supposed that they belonged to another new metal found in samarskite, this time he gave this element the name decipium, after the Latin "decipiens", which means "deceptive, misleading". According to Delafontaine, samarskite contains the earths yttria, erbia, terbia, philippia, decipia, thoria, didymia, and ceria.
This issue was solved in 1879, when Francois Lecoq de Boisbaudran analyzed samarskite and noted that another earth precipitated before didymia when ammonium hydroxide was added. Spectral analysis showed two new blue lines, different from the lines of decipium. Lecoq called the new earth Samaria after its mineral source. The name for the element within became samarium.
Samarium Occurrence
Lanthanide Samarium crustal abundance is 7x10-4 mass %, in seawater 2.3x10-6 mg/L. Along with other rare earth elements it is contained in monazite, bastnasite (0.7-1.3% of Sm2O3), loparite, and samarskite as well as in gadolinite, orthite etc.
Biological role is not clear, however it is known that samarium stimulates metabolism. It is slightly toxic, as other rare earth elements.
Samarium Neighbours
Chemical Elements |