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Properties of the Elements and Inorganic Compounds
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Hydrogrossularite Hydromagnesite Illite Ilmenite Iodyrite Jacobsite Jadeite Jamesonite Jarosite Kainite Kaliophilite Kaolinite Kyanite Lanarkite Lanthanite Laumontite Laurionite Lawsonite Lazulite Lazurite Leadhillite Lepidocrocite Lepidolite Leucite Levyne Litharge Loellingite Maghemite Magnesite Magnetite Malachite Manganite Manganosite Marcasite Marialite Marshite Matlockite Meionite Melilite Mellite Mendipite Mesolite Metacinnabar Microcline Miersite Millerite Mimetite Molybdenite Monazite Monticellite Montmorillonite Montroydite Mordenite Muscovite Nantokite Natrolite Nepheline Norbergite Nosean
Formation of Cu–Au porphyry deposits: hydraulic quartz veins, magmatic processes and constraints from chlorine
Published in Australian Journal of Earth Sciences, 2023
G. N. Phillips, J. R. Vearncombe, J. D. Clemens, A. Day, A. F. M. Kisters, B. P. Von der Heyden
During metamorphism, evaporitic units are modified but can retain Cl-bearing minerals such as scapolite in medium-grade rocks (Almeida & Jenkins, 2017; De Jong et al., 1997; Oliver et al., 1992; Phillips et al., 1994; Yardley & Graham, 2002); and biotite and hornblende have been reported with 5 wt% Cl in meta-exhalites (Oen & Lustenhouwer, 1992). The composition of scapolite can be simplified to a calcic end-member meionite 3(CaAl2Si2O8).CaCO3 and a sodic end-member marialite 3(NaAlSi3O8).NaCl. Heating of evaporite-bearing sequences can yield metamorphic fluids of high salinity, and limited field evidence suggests that scapolite in these assemblages breaks down before the onset of partial melting. Links have been established between evaporitic rocks and some iron oxide–apatite deposits (e.g. Duan et al., 2021), so it would be surprising if such field relations involving scapolite had been missed by researchers working on Cu–Au porphyry deposits. In any case, despite being a major crustal reservoir of Cl (along with oceans and some diagenetic basins), at this stage we lack evidence to link evaporites to all or even most porphyry Cu–Au deposits.