Wiktionary
coesite
n. (context mineral English) A high-pressure polymorph of silica found in extreme conditions such as the impact craters of meteorites, with the chemical composition of silicon dioxide, siliconoxygen2.
Wikipedia
Coesite
Coesite is a form ( polymorph) of silicon dioxide Si O that is formed when very high pressure (2–3 gigapascals), and moderately high temperature , are applied to quartz. Coesite was first synthesized by Loring Coes Jr., a chemist at the Norton Company, in 1953.
Usage examples of "coesite".
And when I reexamined the coesite with the X-ray diffractor, I realized he was right.