pargasite

mineral

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July 1, 2026

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Pargasite is a green or bluish-green hornblende mineral that contains sodium. Hornblende, in general, is a calcium-rich amphibole mineral with a monoclinic crystal structure. Its generalized chemical formula is (Ca,Na)₂(Mg,Fe,Al)₅(Al,Si)₈O₂₂ (OH)₂. Pargasite is one of the end-members of hornblende, with a specific composition of NaCa₂(Mg₄Al)(Si₆Al₂). This mineral is found in high-grade metamorphic rocks.12

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hornblende
edenite, NaCa₂(Mg)₅(Si₇Al); pargasite, NaCa₂ (Mg₄Al)(Si₆Al₂). Extensive solid solution occurs, and each end-member has iron-rich equivalents; minor elements, including manganese, titanium, chromium, potassium, fluorine, and yttrium, are usually present. Hornblendes exhibit typical amphibole structures; these are based on double tetrahedral chains between which four metal sites are located.…
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edenite, NaCa₂(Mg)₅(Si₇Al); pargasite, NaCa₂ (Mg₄Al)(Si₆Al₂). Extensive solid solution occurs, and each end-member has iron-rich equivalents; minor elements, including manganese, titanium, chromium, potassium, fluorine, and yttrium, are usually present. Hornblendes exhibit typical amphibole structures; these are based on double tetrahedral chains between which four metal sites are located.…
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