Noun
coesite (countable and uncountable, plural coesites)
(mineralogy) A high-pressure polymorph of silica found in extreme conditions such as the impact craters of meteorites, with the chemical composition of silicon dioxide, SiO2.
Coesite is a denser polymorph of SiO 2 found in some meteorite impact sites and in metamorphic rocks formed at pressures greater than those typical of the Earth's crust. Source: Internet