Omphacite is a member of the clinopyroxene group of silicate minerals with formula: (Ca, Na) (Mg, Fe 2+, Al) Si 2 O 6. It is a variably deep to pale green or nearly colorless variety of clinopyroxene. It normally appears in eclogite, which is the …

Sericite is name given to very fine, ragged grains and aggregates of white mica – usually muscovite – produced by the alteration of feldspars or other minerals. Included grains of zircon or other radioactive minerals may form pale pleochroic halos in surrounding muscovite.

Omphacite is a clinopyroxene solid solution of jadeite (25%-75%), augite (25%-75%), and aegirine (0%-25%). It is a major mineral component of eclogite along with pyrope garnet and also occurs in blueschist facies and UHP (ultrahigh-pressure) metamorphic rocks.

Omphacite thin section photomicrographs are taken in plane-polarized light and cross-polarized light, and can easily be recognized under the microscope.

Sericite is a common alteration mineral of orthoclase or plagioclase feldspars in areas that have been subjected to hydrothermal alteration typically associated with copper, tin, or other hydrothermal ore deposits.

Named in 1852 by Karl/Carl List from the Greek seirος meaning "silken". A term for a fine-grained white, pale green to oily greenish mica, mainly Muscovite (rarely Paragonite). Neoproterozoic to Quaternary : 670 Ma to 1.3 ± 0.1 Ma - based on 27 recorded ages. A chromium-bearing variety of sericite. See also fuchsite.

Sericite is produced by the alteration of orthoclase or plagioclase feldspars in areas that have been subjected to hydrothermal alteration (also see Sericitic alteration) typically associated with copper, tin, or other hydrothermal ore deposits.

Distinctive Twinning lengthways / Often zoned: typically Anorthite (Ca-rich) centres and Albite (Na-rich) rims. Anorthite cores tend to alter to a fine-grained, turbid, white mica (Sericite) / More commonly found in very high grade metamorphic rocks than in igneous rocks.

Omphacite is a rare member of the pyroxene group. It is intermediary in chemical composition between Augite and Jadeite. It is one of the primary minerals that forms eclogite deposits, which is a dense, course grained rock formed at extremely high pressures. It is occasionally associated with Diamond in Diamond deposits.

Apr 23, 2023 · Sericite is a type of mica, specifically a muscovite mica. The chemical formula for sericite is KAl2(AlSi3O10)(OH)2, which means it contains potassium, aluminum, silicon, oxygen, and hydrogen. Sericite is characterized by its thin, platy structure and is usually white, gray, or pale yellow in color.