In addition to the minerals he discovered himself, Frondel was the honorary namesake of two others: Cliffordite and Frondelite.

During World War II, Frondel worked with the Army Signal Corps to improve the quartz oscillating plates used in walkie-talkies. He was president of the Minerological Society of America in 1956, and spearheaded a project to revise a set of textbooks known as the “data volumes” used widely by minerologists.

Frondel was born in New York City. He attended the Colorado School of Mines, and went on to earn a master’s degree at Columbia University and a doctorate degree at the Massachussetts Institute of Technology.

Frondel’s wife, Judith, a fellow minerologist and frequent collaborator, said that he maintained his sense of humor even as he struggled with Alzheimer’s disease. She said that in his final days he was visited by a steady procession of workers from his nursing home, coming to say goodbye to “their professor.”

“Even in his last stages he was able to make people happy,” she said.

Clifford and Judith Frondel would have celebrated their fifty-third wedding anniversary today.

“We were married 53 years, and we laughed all through those years,” Judith Frondel said.

Frondel is survived by his wife, a daugher, Barbara, who resides in Israel, and a sister, Martita van Ness.