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Milarite
Milarite is a rare beryl. It is a member of the osumilite group. Crystals of this mineral typically come in green or yellow. The mineral gets name after Val Milar. Occurrence The mineral can be found be found in countries like Switzerland, Brazil, Mexico, China, Namibia, and the United States. It can be found in Alpine fissures. the mineral also occurs in marble xenolith A xenolith ("foreign rock") is a rock fragment (country rock) that becomes enveloped in a larger rock during the latter's development and solidification. In geology, the term ''xenolith'' is almost exclusively used to describe inclusions in igne ...s. References Beryllium minerals {{mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beryl
Beryl ( ) is a mineral composed of beryllium aluminium silicate with the chemical formula Be3Al2Si6O18. Well-known varieties of beryl include emerald and aquamarine. Naturally occurring, hexagonal crystals of beryl can be up to several meters in size, but terminated crystals are relatively rare. Pure beryl is colorless, but it is frequently tinted by impurities; possible colors are green, blue, yellow, pink, and red (the rarest). It is an ore source of beryllium. Etymology The word ''beryl'' – enm, beril – is borrowed, via fro, beryl and la, beryllus, from Ancient Greek βήρυλλος ''bḗryllos'', which referred to a 'precious blue-green color-of-sea-water stone'; from Prakrit ''veruḷiya'', ''veḷuriya'' 'beryl' (compare the pseudo-Sanskritization वैडूर्य ''vaiḍūrya'' 'cat's eye; jewel; lapis lazuli', traditionally explained as '(brought) from (the city of) Vidūra'), which is ultimately of Dravidian origin, maybe from the name of Belur o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osumilite
Osumilite is a very rare potassium-sodium-iron-magnesium-aluminium silicate mineral. Osumilite is part of the milarite group (also known as the milarite-osumilite group) of cyclosilicates. Characteristics Osumilite chemical formula is .Don S. Goldman, George R. Rossman (1978): ''The site distribution of iron and anomalous biaxiality in osumilite'', In: ''American Mineralogist'', 63, S. 490-498(PDF, 961 kB)E. Olsen, T. E. Bunch (1970): ''Compositions Of Natural Osumilites'', In: ''The American Mineralogiste'', 55, S. 875 - 879(PDF, 328 kB) It is translucent and the typical coloring is either blue, black, brown, or gray. It displays no cleavage and has a vitreous luster. Osumilite has a hardness between 5-6 on the Mohs hardness scale. The hexagonal crystal structure of osumilite is an unusual molecular make-up. The primary unit is a double ring, with a formula of . Normal cyclosilicate have rings composed of six silicate tetrahedrons; . In a double ring structure, two normal r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fissure Vent
A fissure vent, also known as a volcanic fissure, eruption fissure or simply a fissure, is a linear volcanic vent through which lava erupts, usually without any explosive eruption, explosive activity. The vent is often a few metres wide and may be many kilometres long. Fissure vents can cause large flood basalts which run first in lava channels and later in lava tubes. After some time, the eruption tends to become focused at one or more spatter cones. Small fissure vents may not be easily discernible from the air, but the crater rows (see Laki) or the canyons (see Eldgjá) built up by some of them are. The Dike_(geology)#Magmatic_dikes, dikes that feed fissures reach the surface from depths of a few kilometers and connect them to deeper magma chamber, magma reservoirs, often under volcanic centers. Fissures are usually found in or along rifts and rift zones, such as Iceland and the East African Rift. Fissure vents are often part of the structure of shield volcanoes. Icelan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenolith
A xenolith ("foreign rock") is a rock fragment (country rock) that becomes enveloped in a larger rock during the latter's development and solidification. In geology, the term ''xenolith'' is almost exclusively used to describe inclusions in igneous rock entrained during magma ascent, emplacement and eruption. Xenoliths may be engulfed along the margins of a magma chamber, torn loose from the walls of an erupting lava conduit or explosive diatreme or picked up along the base of a flowing body of lava on the Earth's surface. A xenocryst is an individual foreign crystal included within an igneous body. Examples of xenocrysts are quartz crystals in a silica-deficient lava and diamonds within kimberlite diatremes. Xenoliths can be non-uniform within individual locations, even in areas which are spatially limited, e.g. rhyolite-dominated lava of Niijima volcano (Japan) contains two types of gabbroic xenoliths which are of different origin - they were formed in different temperature and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
