coesite

[ koh-sahyt ]
/ ˈkoʊ saɪt /

noun Mineralogy.

a rare form of silicon dioxide, a denser polymorph of quartz, originally synthesized from quartz at high temperatures and pressures: later discovered in nature.
Compare stishovite.

Origin of coesite

1950–55; named after Loring Coes, Jr., 20th-century American who synthesized it; see -ite1