Coesite (/ ˈ k oʊ s aɪ t /) [3] is a form of silicon dioxide (Si O 2) that is formed when very high pressure (2–3 gigapascals), and moderately high temperature (700 °C, 1,300 °F), are applied to quartz. Coesite was first synthesized by Loring Coes, Jr., a chemist at the Norton Company, in …

Coesite is a very rare mineral that forms in unique ultra high metamorphism usually as a result of meteorite impacts. It was named after American chemist Loring Coes, Jr. (1915-1978), who first synthesized Coesite in 1953 before it was naturally discovered in Barringer Crater in 1960.

Coesite, a high-pressure polymorph (crystal form) of silica, silicon dioxide (SiO2). It has the same chemical composition as the minerals cristobalite, stishovite, quartz, and tridymite but possesses a different crystal structure.

A high-pressure modification of SiO2. In the impact rocks, it may result from subsolidus quartz-to-coesite transformation. An interesting coesite-like ...

2021年8月6日 · Coesite in impact rocks is traditionally considered a retrograde product formed during pressure release by the crystallisation of an amorphous phase (either silica melt or diaplectic glass).

Coesite was synthesized in 1953 and stishovite in 1961. They are named by Sosman (1954) and by Chao et al. (1962) for their discoverers, L. Coes and S. M. Stishov, respectively. The unit cell of coesite has 6 and stishovite has 2 SiO 2 formula units.

THE MINERAL COESITE. Chemistry: SiO2, Silicon Dioxide. Class: Silicate; Group: Quartz. Uses: As an indicator of high pressure crystallization (possibly a meteorite impact) and as mineral specimens. Specimens

Coesite, as a UHP phase of quartz, is an index mineral for UHP metamorphism. The transition pressure from quartz to coesite is above 2.8 GPa (at 600 °C) (Fig. 1 A). In most cases, coesite is preserved as mineral inclusions in eclogite-facies metamorphic minerals.

Coesite. Comments: Coesite inclusion in garnet of eclogite sample (Eur. J. Mineral, 13:567). Location: Ultra high-pressure metamorphic area of the Saidenbach reservoir, Erzgebirge, Germany, where micro-diamond-bearing gneiss occurs. Scale: Scale Bar 50 µm. © Eur. J. Mineral

Coesite, the high-pressure polymorph of SiO 2, hitherto known only as a synthetic compound, is identified as an abundant mineral in sheared Coconino sandstone at Meteor Crater, Arizona. This natural occurrence has important bearing on the recognition of meteorite impact craters in quartz-bearing geologic formations.