New Species of Garnet

A University of Maine graduate student is credited with discovering a significant new species of garnet, named menzerite-Y in honor of the German crystallographer Georg Menzer. Jeffrey Marsh collected the rock sample containing the new mineral in Ontario, Canada, on the southern edge of the Canadian Shield in 2009, while working on his doctorate at UMaine.

Marsh was officially credited with the discovery following publication of a peer-reviewed article by Marsh,  research professor of earth science Edward Grew, and other colleagues in the journal Canadian Mineralogist. Menzerite-Y was officially recognized and approved in 2009 by the Commission on New Minerals and Mineral Names of the International Mineralogical Association.

The new garnet species is significant because it contains unusually high levels of yttrium and other rare earth elements. Although the menzerite-Y garnet is not large or showy, according to professor Grew, who oversaw Marsh’s research on the new mineral, “The size of a new mineral has little bearing on its scientific significance... Far more important than size is the mineral’s significance to science. Jeff’s new mineral is particularly significant because many common garnets, including those found in Maine, contain some yttrium and rare earth elements. [These] are unusually abundant in Jeff’s mineral and make it a new species.”

Yttrium is used in the production of phosphors, such as those in television cathode ray tube displays and in light emitting diodes (LEDs). It is also utilized in production of lasers, electrodes, electronic filters and electrolytes.

Says Marsh of his discovery, “It was certainly exciting… I hadn’t been looking for new minerals at all, but once we realized the potential significance of this find, my collaborators and I jumped into the project headfirst… Beyond the novelty of finding a mineral species that had never been identified before, menzerite’s unique chemical composition has yielded a good amount of information on a previously unknown type of cation substitution — a chemical exchange within a mineral as pressure and temperature conditions change — in garnet group minerals that can better explain a number of observations by other geologists around the world.”

“As a result of Jeff’s discovery,” says Grew, “we now better understand how yttrium and rare earth elements are incorporated in common garnet… In the short time since Jeff’s discovery was published, scientists at the University of Texas and the German Georesearch Center in Potsdam are applying his findings in their own research.”