Metallic Crystals of Bismuth Grown in the Lab

Bismuth, in the form of a hopper crystal

Hopper Crystals are artificially grown crystals, grown either in the lab or at home, mainly for collectors and gem shops. The name ‘Hopper Crystals’ gets its name from the unlikely source of a type of ‘hopper cart’ familiar to farms and in agricultural use. This is a wagon with high sides and steep interior angles that direct the loose contents downwards towards a trap door at the bottom, which is opened for rapid unloading. Railway cars that carry grain, coal, gravel or sand or other heavy bulk materials use the ‘hopper cart’… From: Hopper Crystals of Synthetically-Grown Bismuth: Iridescent Heavy Metal Crystals