• Albite-epidote hornfels facies correlates with the greenschist facies into which it grades with increasing pressure • Hornblende hornfels facies correlates with the amphibolite facies, and the pyroxene hornfels and sanidinite facies correlate with the granulite facies 26. Amphibolite; Amphibolite is a coarse-grained metamorphic rock, predominantly composed of mineral amphibole and plagioclase feldspar. A high-, intermediate-, ar low-pressure-facies … Where possible, the greenschist-facies and the epidote-arnphibolite- and arnphibolite-facies groups are divided into three facies series based on pressure. Muscovite ( Si:Al> 3:1 ) b. Amphibolite Facies: This facies is … Epidote-amphibolite facies assemblage (plagioclase [An 24-36] + hornblende + epidote + sphene + quartz) at the Davis Mill occurrence gives way to the amphibolite assemblage (calcic plagio-clase [An 33-88] + hornblende + garnet + epidote + ilmenite + quartz) at Hudson Rapids. Epidote in an epidote–amphibolite facies basaltic rock. This mineral occurs mostly in various metamorphic rocks (greenschist and amphibolite facies), but it may also crystallize directly from felsic magma. The set of metamorphic mineral assemblages (facies) in which basic rocks are represented by hornblende + albite + epidote. Width of sample 11 cm. Epidote is the term for the optically negative, high birefringence Al-Fe 3+ epidote, and is the most common epidote type. is a region of sta-bility of the staurolite-bearing mineral assemblages in. Basic rocks metamorphosed to the amphibolite facies are amphibolites, containing mostly hornblende and plagioclase. These amphibolites consist of an epidote–amphibolite facies assemblage of amphibole, garnet, albite, clinozoisite, paragonite, ilmenite and quartz, which is incompletely overprinted by an eclogite facies assemblage of garnet, omphacite and rutile. Equivalent to Eskola's epidote-amphibolite facies, it is of uncertain status, transitional between the greenschist facies and the amphibolite facies. Arendal, Norway. Omphacite and garnet coronas around amphibole occur in amphibolites in the Hong'an area, western Dabie Mountains, China. Fig. Greenschist facies: chlorite + epidote + albite (actinolite, biotite) Amphibolite facies: plagioclase + hornblende (epidote, garnet, orthoamphibole, cummingtonite) Granulite facies: orthopyroxene + plagioclase (clinopyroxene, hornblende, garnet) Temperature-pressure diagram The epidote–amphibolite facies. 25.2. The mineral assemblages of green-schist facies include chlorite, chloritoid, epidote, actinolite, muscovite, albite (anorthite< 7% ) and quartz. the field of chlorite stability in metapelites, while. 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