Pyroxene Thin Section

Perpendicular to their cleavage planes pyroxenes have nearly square cross sections which together with the cleavage directions are diagnostic properties.
Pyroxene thin section. Approximatly 90ยบ cleavage planes. Thin irregular and wavy lamellae common. The fine grained gray rock in this image is the host basalt.
Pyroxene in basal section and isotropic laucite crystals in a basanite. The result of unmixing in the ca mg fe pyroxenes is commonly visble in thin section as set of thin exsolution lamellae. Parallel extinction in longitudinal sections pale pink to green pleochroism.
Ppl image 10x field of view 2mm hourglass zoning in a pyroxene. Augite mg fe ca al 2 si al 2o6 thin section. Colourless pale green pale brown two cleavages intersect at 90 o moderate relief moderate order interference colours equant crystal shape common minerals that might be confused with pyroxene and occur in similar rocks.
Key optical features of pyroxene in thin section. Biaxial 2v 25 70. Orthopyroxene high in mg is common in gabbro and peridotite groups.
Simple twin in basal section of clinopyroxene. Xpl image 10x field of view 2mm twinned pyroxene crystal in a tephrite from latium italy. Xpl image 10x field of view 2mm hourglass zoning in a pyroxene.
Acicular crystals of cr diopside. A thin section of green pyroxene mantle peridotite xenolith from san carlos indian reservation gila co arizona usa. Sub ophitic texture with clinopyroxene and plagioclase altered to clay xpl.