Mineralogist Charles (Charlie) Prewitt peacefully passed away at home on April 28, 2022, at the age of 89.

Prewitt’s distinguished career reflects the diversity and impact of the mineral sciences. Following a bachelor’s degree in geology from the Massachusetts Institute of Technology, Prewitt remained in Cambridge to pursue advanced degrees under Martin Buerger. His Ph.D. thesis on the crystal structures of wollastonite and pectolite was completed in 1962. Immediately following his doctorate, Prewitt joined DuPont as a research scientist. There, in collaboration with Bob Shannon, he developed the crystal chemical systematics that led to the much-cited revised values of effective ionic radii. From 1969 to 1986 Prewitt was professor of crystallography at the Stony Brook campus of the State University of New York, where he began one of the country’s preeminent programs in crystal chemistry and high-pressure research and nurtured the careers of many outstanding graduate students.

Prewitt’s tenure was distinguished by extensive service to the science community, including membership on U.S. National Committees on Geology and on Crystallography, and serving in several different offices in the Mineralogical Society of America, including president in 1983–1984. It was also during this period that he forged important international ties through visiting professorships in Japan, Australia, and the United Kingdom. In the process, he was instrumental in establishing the new field of mineral physics. He was also one of the founding editors of the journal Physics and Chemistry of Minerals.

— Portions of text courtesy of the Geological Society of America