Clear rock crystals are occasionally found at prehistoric sites in the British Isles, but very little research into their significance has been done until now. A new study suggests that these rare crystals were used to mark burial sites. According to Nick Overton, “The crystals would have looked very unusual in comparison to other stones they used, and are extremely distinctive as they emit light when hit or rubbed together and produce small patches of rainbow—we argue that their use would have created memorable moments that brought individuals together, forged local identities and connected the living with the dead whose remains they were deposited with.”