When I was little and first fell in love with the stars in the sky, it was always easy to spot the constellation Cassiopeia at night — just look for five dots that looked like the letter “w” as the throne for Cassiopeia, queen of Aethiopia. But apparently the Germans had a thing for Cassiopeia too, because an Austrian, a Frenchman and an American all independently discovered the element Lutetium at the same time… After years of debate, the Frenchman won the naming rights for Lutetium, but the Germans still stuck with Cassiopeia for their name-of-choice through the nineteen fifties.
But I don’t know, maybe this element Lutetium was the perfect thing for queen Cassiopeia, because although it is more common than silver here on Earth, it’s hard to separate from other elements, and it’s harder and denser than it’s counterparts (even costing ten thousand dollars per kilogram).
If I could have photographed queen Cassiopeia, I may have wanted Lutetium aluminum garnet as the liquid element in immersion lithography for added depth-of-focus in my photo journalism travails… Though maybe I should just savor the connection between queen Cassiopeia (with her throne in the sky), the mother of Andromeda (goddess and galaxy), and Lutetium — something that has always been so strong, and has also worked with others, to help us see everything so much better…
* Germans used cassiopium (Cp), after the constellation Cassiopeia, as the name for element 71 (Lutetium) until the 1950s. Lutetium is not a particularly abundant element, though significantly more common than silver in the earth’s crust; it has few specific uses, but is found with almost all other rare-earth metals but never by itself. Lutetium is very difficult to separate from other elements, and pure Lutetium metal is very difficult to prepare. Even though it is more common than silver, it is one of the rarest and most expensive of the rare earth metals with the price about US$10,000 per kilogram, or about one-fourth that of gold. Lutetium also has the highest density, melting point, and hardness of the lanthanides. For an application for Lutetium: Immersion lithography is a photolithography resolution enhancement technique for manufacturing integrated circuits (ICs) that replaces the usual air gap between the final lens and the wafer surface with a liquid medium that has a refractive index greater than one. Currently, the most promising high-index lens material is Lutetium aluminum garnet.