Tiny diamond grains discovered in high-grade metamorphic rocks (gneisses) from south-western Norway may force geologists to rethink cherished ideas about the Earth's continental crust and processes. Discovered by an international team of Russian, Norwegian, British and US geoscientists, the diamond fragments at only 20–80 micrometres in size are too small to see without a microscope. Yet they have formed within the continental crust where they shouldn't have! ... ...
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