Hunting for shiny, rainbow-coloured gemstones, miners found a different kind of treasure — a wonderfully preserved fossil skeleton of an ancient sea monster. The marine reptile lived 70 million years ago — at the same time as the dinosaurs — and was unearthed from a part of Alberta, Canada, that used to be underwater. The skeleton of the fearsome predator has, rarely, been very well preserved, with only its flippers missing.