EuroGraphics Minerals 1000-Piece Puzzle. Of the approximate 4,000 minerals, each with their own characteristic chemical composition, highly ordered atomic structure, and specific physical properties, 40 of the most well known are illustrated. These include gold, diamond, sulphur, copper and quartz. Strong high-quality puzzle pieces. Made from recycled board and printed with vegetable based ink. This superior quality puzzle will delight and educate all at the same time.