significance. There are no common uses for this mineral, and it is not used for the fabrication of any known products. The characteristics that make donnayite special are its small size, and the few locations on Earth at which this mineral can be found. It requires a unique environment to form and crystallize, and for this reason donnayite has only been found in three countries of the world. Another characteristic that makes donnayite unique is the fact that it contains the REE, yttrium, as an essential constituent. Although donnayite has no known human uses, it has other characteristics that make it distinct and for this reason most people do not even know this mineral exists. Name Donnayite was named in honor of Joseph Desire Hubert Donnay, and his wife, Gabrielle Donnay (Baker et al., 1978). J. D. H. Donnay (1902–1994) was an accomplished Belgian-American-Canadian crystallographer and mineralogist, and professor at Johns Hopkins University. He served as president of the Mineralogical Society of America and in 1971 was awarded its highest honor, the Roebling Medal. Donnay emphasized the importance of optical mineralogy and crystal morphology and how they related to crystal structure. He is the author of 100 abstracts, 148 papers, 36 books (or chapters in books), 38 reviews, and several non-scientific papers. His wife, Dr. Gabrielle Donnay, was a professor of crystallography at McGill University in Montreal, Canada where Dr. J. D. H. Donnay later became Research Associate and a guest professor. References External links Dr. JDH Donnay Carbonate minerals Triclinic minerals Minerals in space group 1