Chamosite is the Fe2+ end member of the chlorite group. A hydrous aluminium silicate of iron, which is produced in an environment of low-to-moderate-grade metamorphosed iron deposits, as grey or black crystals in oolitic iron ore. Like other chlorites, it is a product of the hydrothermal alteration of pyroxenes, amphiboles and biotite in igneous rock. The composition of chlorite is often related to that of the original igneous mineral, so that more Fe-rich chlorites are commonly found as replacements of the Fe-rich ferromagnesian minerals (Deer et al., 1992).
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Chamosite is the Fe2+ end member of the chlorite group. A hydrous aluminium silicate of iron, which is produced in an environment of low-to-moderate-grade metamorphosed iron deposits, as grey or black crystals in oolitic iron ore. Like other chlorites, it is a product of the hydrothermal alteration of pyroxenes, amphiboles and biotite in igneous rock. The composition of chlorite is often related to that of the original igneous mineral, so that more Fe-rich chlorites are commonly found as replacements of the Fe-rich ferromagnesian minerals (Deer et al., 1992).
== History == In 1820, Pierre Bertier, a mineralogist and mining engineer from Nemours, France, discovered chamosite. The new mineral was found in an area of low-to-moderate-grade metamorphosed iron deposits. Early samples of chamosite (which is a chlorite) stirred some controversy after they were found to possess the structure of kaolin rather than chlorite; however, further research proved that chamosite was found in nature largely alongside another phyllosilicate called berthierine, which has a kaolin-type structure and is rather difficult to distinguish from chamosite. Chamosite is named after the municipality of Chamoson, between Sion and Martigny, in the canton of Valais, Switzerland.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).