Dolerite (Scourie Dyke). Lewisian. Scotland.

This is a thin section microscope slide of Scourie Dyke material from Scourie, North West Highlands of Scotland. Thought to be 2390 million years old, (give or take a year or two), cutting even more ancient Lewisian Gneiss, and getting on for half the age of planet earth. Some of the most ancient rocks found anywhere. The Scourie Dykes are world famous. Essentially a dolerite, containing plagioclase, remarkably unaltered, nicely twinned and zoned, some showing curving due to subsequent strain, pyroxene and magnetite both rimmed with hornblende, and a little quartz. Essential part of any serious collection.

1 Slide

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