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Three polytypes of chrysotile are known. [8] These are very difficult to distinguish in hand specimens, and polarized light microscopy [6] must normally be used. Some older publications refer to chrysotile as a group of minerals—the three polytypes listed below, and sometimes pecoraite as well—but the 2006 recommendations of the International Mineralogical Association prefer to treat it as ...
The most common asbestiform mineral is chrysotile, commonly called "white asbestos", a magnesium phyllosilicate part of the serpentine group. Other asbestiform minerals include riebeckite, an amphibole whose fibrous form is known as crocidolite or "blue asbestos", and brown asbestos, a cummingtonite-grunerite solid solution series.
Serpentinization is a form of low-temperature (0 to ~600 °C) [5] metamorphism of ferromagnesian minerals in mafic and ultramafic rocks, such as dunite, harzburgite, or lherzolite. These are rocks low in silica and composed mostly of olivine ( (Mg 2+ , Fe 2+ ) 2 SiO 4 ), pyroxene ( XY(Si,Al) 2 O 6 ), and chromite (approximately FeCr 2 O 4 ).
Lizardite, chrysotile, and antigorite all have approximately the formula Mg 3 (Si 2 O 5)(OH) 4 or (Mg 2+, Fe 2+) 3 Si 2 O 5 (OH) 4, but differ in minor components and in form. [10] Accessory minerals, present in small quantities, include awaruite, other native metal minerals, and sulfide minerals. [12] Ophiolite of the Gros Morne National Park ...
Antigorite is the polymorph of serpentine that most commonly forms during metamorphism of wet ultramafic rocks and is stable at the highest temperatures—to over 600 °C (1,100 °F) at depths of 60 km (37 mi) or so. In contrast, lizardite and chrysotile typically form near the Earth's surface and break down at relatively low temperatures ...
Lizardite contains H 2 O in excess of the nominal formula, as does chrysotile. It has a high amount of Fe 2 O 3 and a low amount of FeO. [9]: 8 One study found that lizardite has a high amount of SiO 2 and a low amount of Al 2 O 3. [10]: 193
Antigorite is a lamellated, monoclinic mineral in the phyllosilicate serpentine subgroup with the ideal chemical formula of (Mg,Fe 2+) 3 Si 2 O 5 (OH) 4. [2] It is the high-pressure polymorph of serpentine and is commonly found in metamorphosed serpentinites.
Chrysolite may refer to: . Peridot, a gem-quality olivine; Archaically, any of several green or yellow-green-coloured gemstones including Topaz, a silicate mineral of aluminium and fluorine