hornblende (redirected from Hornblend)

hornblende: see amphibole.

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hornblende

Any of a subgroup of amphibole minerals that are calcium-iron-magnesium-rich and monoclinic in crystal structure. Hornblende, whose generalized chemical formula is (Ca,Na)₂(Mg,Fe,Al)₅(Al,Si)₈O₂₂(OH)₂, occurs widely in metamorphic and igneous rocks. Common hornblende is dark green to black in colour and usually found in middle-grade metamorphic rocks (formed under medium conditions of temperature and pressure). Such metamorphic rocks with abundant hornblende are called amphibolites.

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hornblende

a black or greenish-black mineral of the amphibole group, found in igneous and metamorphic rocks. Composition: calcium magnesium iron sodium aluminium aluminosilicate. General formula: (Ca,Na)_2.3(Mg,Fe,Al)₅Si₆(Si,Al)₂O₂₂(OH)₂

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hornblende [′hȯrn‚blend]

(mineralogy)

A general name given to the monoclinic calcium amphiboles that form an extensive solid-solution series between the various metals in the generalized formula (Ca,Na)₂(Mg,Fe,Al)₅(Al,Si)₈O₂₂(OH,F)₂.