I'm actually working on this at the moment. It's fascinating: in or around 1300BC the Deverel–Rimbury culture prompted the mining of copper on the Orme. It’s likely that copper mining was being carried out around 2000BC since bronze artefacts have been unearthed in Wilmslow, dating back to 2000BC.
It all seems to have started around 450 million years ago. Around 450 million years ago, North Wales was home to a super volcano, with the caldera centred on Snowdon. As the huge, super continents of Laurasia and Gondwana moved towards each other to form Pangea, the landscape of North Wales was crumpled and compressed, to form not only a great super volcano but mountains higher than today’s Himalayas.
Move on 100 million years, to the period that gave the Earth its coal reserves, swamplands and dragonflies with three foot wingspans, and we see how the Orme rose from the warm, milky seas that abounded during that period, adding layer upon layer of the skeletonic remains of Cretaceous wildlife.
The Orme, as we all know, is Limestone, and together with the crumpling effect from the 400m year BC tectonic plate fissures, trillions of creatures during the Cretaceous period died, their skeletons contributing to the Orme's structure.