It is also known as Celestine, and is named after the Latin word for 'sky' or 'heaven', and in ancient culture it was said to be pieces of the sky that had fallen to earth. It is usually found in a delicate blue colour but can also be found in other colours. Celestite is a strontium sulfate, which was first recorded in the 1790s. It is a relatively soft mineral and as such is rarely used for jewellery. Celestite is a primary ore for Strontium, which is used to manufacture fireworks and pyro as it creates a bright red flame. Celestite holds the record for largest geode in the world, 35 feet wide with crystals up to 3 feet wide. It is located 30-40 feet below the surface on South Bass Island in Ohio on a winery that they discovered in 1897 whilst drilling for a well. 12,000-15,000 years old. You can go and visit it, Crystal Cave, although its smaller than it initially was as some crystals were taken out to create fireworks. Tours of the cave saved the winery from closure during Prohibition. Madagascar has yielded some of the best Celestite crystals for over 50 years, in a village called Sakoany in the northwest of Madagascars coast. They form in cavities in the sandstone, producing bigger geodes the further they dig. They're hand dug in lots of small pits between 5-10 metres wide, and they can only dig during the dry season (May to October), otherwise the pits just fill with water.