A Geoscience Digital Image Library

TitleThin section of alkalic syenite
DescriptionThin section of alkalic syenite in plain polarized light. Strongly developed flow texture from the subparallel orientation of slender feldspar laths; clear sodic orthoclase (carlsbad twinning) and turbid sodic plag. (fine albite twinning). A few blocky nepheline grains, and scarce anhedra of sodalite (isostropic) also appear. Pale green augite with narrow bright green (aegirinitic) rims is the main mafic, forming euhdra of varying biotite and include numerous magnetite grains. The other accessories are abundant anhedral sphene and apatite crystals.
LocationUSA ▹ Colorado ▹ Teller. Near Victor. Golden Cycle Mine.
PhotographerDarla Sondrol. 2002-04-02.
CollectionWard’s Collection of Classic North American Rocks #14.
Key wordsalkalic, syenite, Colorado
Tech details1.15 MB. Thin section. Nikon FDX-35.
GeoDIL number2555