Augite In Thin Section

Clinopyroxenes and orthopyroxenes are easily distinguished in thin section by their extinction angles.

Augite in thin section. This is called incomplete extinction or sometimes birds eye maple extinction. Simple and lamellar twinning on 100 and 001. Clinopyroxenes have inclined extinction and orthopyroxenes have parallel extinction.

Small 250x250 max medium 500x500 max. Augite thin section photomicrographs are taken in plane polarized light and cross polarized light and can easily be recognized under the microscope. 100 sections show parallel extinction.

The calcium content of augite is limited by a miscibility gap between it and pigeonite and orthopyroxene. Augite is a solid solution in the pyroxene group. Elongated k 001 acicular skeletal dendritic.

Augite is a clinopyroxene. Or anomalous blue brown extinction angle. Stubby prismatic crystals square or octagonal in section to 10 cm.

Augite ca na mg fe al ti si al 2o6 c 2001 mineral data publishing version 1 2 crystal data. Xpl image 2x field of view 7mm pyroxene in basal section vulcano island italy. Diopside and hedenbergite are important endmembers in augite but augite can also contain significant aluminium titanium and sodium and other elements.

Note the simple twin. Augite phenocryst in k 84 showing 90 degree cleavage. 90 degree cleavage visible in thin section.