1879

Samarium

• Lecoq isolated impure samarium oxide
• from the radioactive mineral samarskite,
• which contains yttrium and cerium, uranium and iron,
• niobium, tantalum, titanium, and oxygen, named after
• Vassili Samarsky-Bykhovets, who had been
• a mining engineer in the Russian military.
• *
• Although Lecoq’s samarium oxide
• contained a bit of europium (found later),
• his spectral analysis showed two new blue lines
• that established it against a flurry of competing claims.
• *
• J. Lawrence Smith thought he had found a new element
• in samarskite, but it was a mix of terbium and holmium.
• Marc Delafontaine thought he had found
• another in samarskite but it was holmium.
• Delafontaine identified a second new element in samarskite,
• but it was later shown to be a mix of rare earths
• including samarium, neodymium, and praseodymium.
• Jean Charles Galissard de Marignac said he found
• two new elements in samarskite but one was samarium
• and the other . . . well, more on that later.

Atomic number 62

• More common than tin
• just harder to isolate,
• samarium makes strong magnets
• when alloyed with cobalt.
• Samarium a minor component
• of mischmetal in lighter flints.
• Samarium(III) triflate
• an efficient Lewis acid catalyst.
• Samarium added to glass
• helps absorb infrared.
• Samarium-153 a radiation source
• kills cancer cells.

Doable stuff

• The samarium-cobalt magnet
• was not developed
• until the early 1970s.
• Samarium is only slightly toxic,
• and part of an enzyme
• involved in DNA replication and repair.
• OK. The story of samarium
• seems to tell us
• that we may fumble.
• It may take us a long time;
• it may be difficult and uncertain,
• but an ideal is reachable.