#luxullianite — Public Fediverse posts

Some larger #schorl #tourmaline crystals I managed to find inside some #luxullianite. Tourmaline is recognisable by it's long prismatic 'habit', the crystals also have a tendency to change colour along their length. Big ones are valuable as gemstones and apparently they might have been used as navigational aids for #Vikings (used to detect the sun's position pre-dawn or in cloudy conditions).

This is called #luxullianite - a rare rock (globally if not locally), shiny pink orthoclase crystals embedded in dark tourmaline called schorl. Part of the massive granite backbone that forms #Cornwall. Orthoclase is not limited to earth, as it has also been found on Mars. Strictly speaking, not technically #fossicking as this sample came from Mousehole beach.