Metasandstone. Isle of Rum, Scotland

This is a thin section microscope slide of a baked sandstone rock from the Isle of Rum in the Inner Hebrides. Usually known for it's ultramafic rocks this island has quite a variety of different rock types. This was originally a arkose torridonian sandstone, and has been altered and completely recrystalised by a nearby picrite volcanic neck of tertiary age (calculated to have been at 700m depth at the time). The rock shows vague spherulitic structure and numerous needles. The texts talk of quartz paramorphs after tridymite.

1 Slide

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