- Phillipsite
Phillipsite is a mineral of the
zeolite group; a hydratedpotassium ,calcium andaluminium silicate, approximating to (Ca,Na2,K2)3Al6Si10O32·12H2O. (Also with sodium replaced by calcium: KCaAl3Si5O16·6H2O [ [http://mineral.galleries.com/minerals/silicate/phillips/phillips.htm PHILLIPSITE (Hydrated Potassium Calcium Aluminum Silicate) ] ] ). The crystals aremonoclinic , but only complex cruciform twins are known, these being exactly like twins ofharmotome . Crystals of phillipsite are, however, usually smaller and more transparent and glassy than those of harmotome. Spherical groups with a radially fibrous structure and bristled with crystals on the surface are not uncommon. TheMohs hardness is 4.5, and thespecific gravity is 2.2. The species was established by A. Levy in 1825 and named after William Phillips. French authors use the name christianite (afterChristian VIII ofDenmark ), given by A. Des Cloizeaux in 1847.Phillipsite is a mineral of secondary origin, and occurs with other zeolites in the amygdaloidal cavities of
mafic volcanic rock s: for example in thebasalt of theGiants Causeway in County Antrim, and nearMelbourne in Victoria; and in Lencitite nearRome . Small crystals of recent formation have been observed in the masonry of the hot baths at Plombires and Bourbonneles-Bains, inFrance . Minute spherical aggregates embedded in redclay were dredged by theChallenger from the bottom of the CentralPacific , where they had been formed by the decomposition oflava .ee also
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List of minerals
*List of minerals named after people References
*1911
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