New mineral named for late Professor Charles V. Guidotti

The late Charles V. Guidotti, Professor in the U Maine Department of Earth Sciences from 1981 to his untimely death in 2005, has been honored with having a new mineral, guidottiite, named after him. This name was approved by the Commission on New Minerals and Mineral Names of the International Mineralogical Association, which has officially recognized the discovery of this new mineral. The naming of new minerals follows a complex protocol and careful scientific review by the Commission, which consists of 38 officers and members from 34 countries. It is a signal honor for a mineral to be named for an individual.

Guidottiite is a new manganese mineral in the serpentine group discovered in the Kalahari manganese deposit in South Africa. Its grains are no larger than ⅛ of an inch across, black in color with a glassy luster. It splits easily into the thin sheets. So far the mineral is only known from the one locality in South Africa, but now that it has been reported and characterized in the scientific literature, it is possible that mineralogists will be able to find it in other locations in the world.

Serpentine-group minerals belong to the class of layer or sheet silicates, which also includes micas, chlorites, and clays, and were a special focus of Prof. Guidotti’s mineralogical career. He co-authored many scientific papers on sheet silicates, which are familiar to many residents of Maine as the shiny flakes of mica found in schist and granite throughout the state. He also had an interest in manganese minerals found in small deposits in Maine, so a manganese serpentine is a particularly appropriate choice for a mineral to bear his name.

The scientific paper officially reporting guidottiite was published this year in Clays and Clay Minerals, vol. 58, p. 364-376 under the title “Guidottiite, the Mn-Analogue of Cronstedtite: A New Serpentine-Group Mineral from South Africa,” by Michael Wahle, Thomas Bujnowski, Stephen Guggenheim from the University of Illinois at Chicago, and by Toshihiro Kogure from the University of Tokyo. Guidottiite was Wahle’s master’s thesis project. Bujnowski, also a Master’s student, is married to Michelle Fiscus, who graduated from U Maine in 2006. Guggenheim did a Ph.D. thesis under Guidotti when he was a professor at the University of Wisconsin between 1969 and 1981. Dr. Martin Yates, Laboratory Manager in the Department of Earth Sciences, contributed to the study with chemical analyses of guidottiite that he carried out on the electron microprobe at the University of Maine. Prof. Guidotti devoted his career to mineralogical research and the education of students at the University of Maine, and it is indeed fitting that his name has been given to a new mineral.