August 7, 2011

Geology Word of the Week: J is for Jimthompsonite

Posted by Evelyn Mervine

Jim Thompson, circa 1979. Image taken from American Mineralogist, 1979, vol. 64: 664.

def. Jimthompsonite:
1. A magnesium and iron-rich silicate mineral found between the chlorite and actinolite zones of a metamorphosed ultramafic body. Jimthompsonite has the formula (Mg,Fe)5Si6O16(OH)2 and an orthorhombic structure. The mineral was named after James Burleigh Thompson, Jr., an eminent mineralogist and petrologist.
2. A wonderful example of scientists having fun with naming– and, in the process, classifying and better understanding– the world around them.

Intermixed jimthompsonite and clinojimthompsonite from Chester, Vermont. Photo by Jeff Weissman and taken from here:

Jimthompsonite is a delightfully ridiculous mineral name. Minerals are often named after people, usually for the people who first discovered them. For example, searching randomly through my mineralogy book, I come across mineral names such as Pentlandite (named for Joseph Barclay Pentland), Vivianite (named for John Henry Vivian), and Covellite (named for Nicola Covellite).

Minerals are also commonly named after places, often their “type locality,” a notable place where the mineral occurs or was first discovered. For example, Andalusite is named for Andalusia, Spain. Mineral names are also sometimes taken from colloquial, historical names– sometimes modified– which existed prior to the mineral being classified scientifically. For example, Beryl comes from Ancient Greek.

Sometimes, minerals that are named in honor of people end up with ridiculous names such as “jimthompsonite.” Why jimthompsoite? Well, thomsonite was already taken, and I suppose thompsonite and thomsonite would have been somewhat confusing. Jamesonite was also already taken. I suppose jamesthompsonite was a slightly more formal option, but for whatever reason the mineral namers went with jimthompsonite, which is simply delightful and probably more reflective of Prof. Thompson, who apparently went by Jim rather than James.

Jimthompsonite? Sounds like something Tintin detectives Thompson and Thomson should investigate!

What’s an even more ridiculous mineral name than jimthompsonite? Clinojimthompsonite, also named after Jim Thompson.

Ridiculous scientific names are not just limited to minerals. Just look at some of the ridiculous Element names (for example, Californium) and asteroid names (for example, #12426 is named “Raquetball”). Isn’t discovering and naming things fun? One of the funnest parts of science, I think.

Here are a few more ridiculous and fun mineral names:

Armalcolite: A mineral discovered on the moon and named for astronauts Armstrong, Aldrin, and Collins.

Znucalite: A mineral rich in the elements Zn, U, and Ca. Sounds like a Dr. Suess mineral, doesn’t it?

Cummingtonite: Supposedly named for the town of Cummington, Massachusetts. Uh-huh.. sure… 🙂

Coffinite: A halloween mineral? It’s uranium-rich and radioactive, so be careful…