Dartington Crystal Glassware. Whatever the drink or occasion – make it special with a crystal drinking vessel handmade in Devon. At Dartington Crystal each piece is a true original. Individually made by a team of up to 12 craftsmen led by a master glassblower who has perfected his skills over at least 10 years. The raw materials of crystal (sand, lead oxide and other compounds) are melted in a clay pot within a special furnace at 1400 degrees.