Element of the Month: Erbium!

March's Element of the Month:

Erbium!
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Atomic Mass: 167.259 amu
Melting Point: 1529 °C
Boiling Point: 2868 °C

It's been a few years since we mentioned the Ytterby Element-Discovery Juggernaut, so let's briefly rehearse it here. Ytterby is a small village on one of the islands around Stockholm. It had a little quarry.

The humble Ytterby quarry, today.

In the late nineteenth century, when brainy chemists got really excited about filling in the blanks in Dmitri Mendeleev's famous spreadsheet, the Ytterby quarry turned out to be a real gold mine for Swedish scientists from the nearby capital. Well, not a gold mine. Rather, a new-element mine.  In arguably monomaniacal homage to the village of their discovery, they gave the new elements names like Ytterbium and Yttrium and Terbium and, in the case of our element of the month, Erbium.  (When they ran out of permutations of Ytterby, they moved on to Holmium (as in Stockholm), Thulium (as in "Thule," ie. Sweden), and Gadolinium, for which they finally gave up on geography and honored a famous brainy guy.)

Erbium is one of the lanthanide elements, the ones we're not supposed to call "rare earths," and like most of them it is not so much incredibly rare as incredibly hard to isolate.  It reacts amiably with almost every substance in nature -- air, water, and the like -- so it is never found in a pure state.  In fact, it took more than 90 years between the "discovery" by Carl Gustaf Mosander in 1843 and the first time anybody could really cook up a chunk of pure Erbium, in 1934. 

The Centerfold!

Once you get it good and pure, Erbium is a silvery metal like most of the other elements.  Many of its chemical compounds, however, are a fetching pink, or violet.  That means that one of its modern uses is as a colorant in extremely expensive art glass.

Erbium is also useful in dental surgical lasers, which can perform many of the tasks usually done with dental drills, except better, and at twenty times the expense!

Throw in a few specialized metallurgical uses -- Erbium can alloy Vanadium to make it more workable, for instance -- and you are well on your way to knowing your way around Erbium's place in the modern human economy.  Which means you're better off then you were before you read this little precis.

Dale Chihuly, Erbium Chandelier with Gilded Putto, 1993. Corning Museum of Glass.