When Christine Clark set out for a Boxing Day walk along the beach on Holy Island in northern England, she was simply hunting for the small disc-shaped fossils that locals have been lovingly collecting on that stretch of coast for over a thousand years. But something entirely unexpected stopped her right in her tracks: a tiny pebble nestled in the sand appeared to be smiling back at her. What she had stumbled upon turned out to be a 350-million-year-old fossil from an ancient sea creature, curved and split in just the right way to look strikingly like a grinning set of teeth. She posted a photo to a fossil identification page on Facebook, and within days the little smiling rock had collected thousands of delighted likes and comments from people all around the world.
Scientists at the British Geological Survey confirmed the fossil belongs to a crinoid, a marine animal that first appeared on Earth more than 500 million years ago and still has living relatives in our oceans today. Known affectionately as sea lilies, crinoids have graceful branching arms that fan out like flowers from a long flexible stem anchored to the sea floor, and what Christine found was a curved section of that stem, naturally split to create its unforgettable smile. Holy Island itself has a wonderfully deep and magical history with crinoid fossils: locals have been collecting the small round disc pieces since the 1300s, once believing that the beloved monk and saint Cuthbert was crafting them by hand as spiritual gifts from beyond. Christine has received offers to purchase her one-of-a-kind grinning fossil but plans to keep it, saying with a smile of her own that it simply brings far too much joy to far too many people.