|Gwithian Towans and beach|
But the history of these rocks takes us even further back into geological time, to the formation of Pangea itself in the late Carboniferous/early Permian period. Around 300 million years ago ancient continents were finally coming together into the single supercontinent and the unimaginable tectonic forces forged a new mountain range and partially melted the underlying mantle, which crystallised into igneous granite, which underlies all these rocks. These cliffs are the roots of the ancient Variscan mountain range, remnants manifesting themselves today as the Urals, the Pyrenees, and in SW England the high moors of Dartmoor and Bodmin.
The intense heat and pressure metamorphosed the sediments into a hard vitreous rock, known locally as killas, and as this cooled it cracked and the cracks were later filled with hot hydrothermal fluids, containing minerals, quartz in this area but a couple of miles inland the tin and copper minerals which would be mined millennia later.
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