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Pigeonite is a
mineral in the
clinopyroxene subgroup of the
pyroxene group. It has a
general formula of (Ca,Mg,Fe)(Mg,Fe)Si2O6. The
calcium cation fraction...
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calcium content prevents the
formation of the
orthorhombic phases and
pigeonite ([Mg,Fe,Ca][Mg,Fe]Si2O6) only
crystallises in the
monoclinic system. There...
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calcium content of
augite is
limited by a
miscibility gap
between it and
pigeonite and orthopyroxene: when
occurring with
either of
these other pyroxenes...
- of basalt. In
tholeiitic basalt,
pyroxene (augite and
orthopyroxene or
pigeonite) and calcium-rich
plagioclase are
common phenocryst minerals. Olivine...
- 2O 6) and augite, and
partial solid solutions with
orthopyroxene and
pigeonite. It
forms variably colored, but
typically dull
green crystals in the monoclinic...
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Enstatite –
orthoferrosilite series Enstatite – MgSiO3
Ferrosilite – FeSiO3
Pigeonite – Ca0.25(Mg,Fe)1.75Si2O6
Diopside –
hedenbergite series Diopside – CaMgSi2O6...
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similar parent body. They are
mostly composed of calcium-poor pyroxene,
pigeonite, and calcium-rich
plagioclase (anorthite).
Based on
differences of chemical...
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source of non-****ulate eucrites.
Plutonic rocks consisting of pyroxene,
pigeonite and plagioclase, the
source of ****ulate eucrites.
Plutonic rocks rich...
- history: (1)
crystallization of
twinned pigeonite,
followed by
exsolution of augite; (2)
breakdown of
pigeonite to
orthopyroxene plus augite; (3) exsolution...
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clinopyroxene and plagioclase, with
minor iron-titanium oxides.
Orthopyroxene or
pigeonite may also be
present in
tholeiitic basalt, and olivine, if present, may...
