Add to your crystal collection with one of these fine bismuth specimens . When bismuth crystalises rapidly, the striking stepped 'hopper crystal' formations seen here are created. The intricate crystal structure shimmers with iridescent colours . Display this specimen alone or as a sparkling accent to crystals such as quartz and amethyst. For its uncommon crystals and metallic colour, this bismuth specimen makes a wonderful gift , even for those with the most complete crystal collections.