50 grams (1.76oz) Approximate dimensions: 1 3/4" X 1 5/8" X 1 1/2"
This particular crystal is listed for $9.00
Bismuth is element #83 on the Periodic Table of Elements. It is known as a post-transition metal. It has a relatively low melting-point of about 520 degrees F, which makes it easy to work with. Bismuth crystals form when the metal begins to cool from a molten state. The iridescent colors that bismuth crystals are known for are the result of an oxide tarnish.
Although it is relatively easy to make bismuth crystals, making high-quality crystals is a bit more difficult. First, you need several pounds of bismuth (99.99% pure). Second, a heating process. It can be done on a kitchen stove, but it is better to use a lab-quality heat plate so that you can control the temperature. Third is the extraction method. How you extract the crystals from the molten metal directly affects the types of crystals you create. Lastly, the cooling method. How quickly or slowly the crystal cools determines its colors.
I also sell bismuth crystal fragments in 10oz lots for jewelry/art projects.