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How to Make Bismuth Crystals

Bismuth, element number 83 on the periodic table of elements, grows as square, iridescent crystals with smooth outside edges and a stair-step pattern on the inner edge. Crystals grown this way are called hopper crystals. Their iridescent color pattern forms from an oxide layer on the outside of the crystals. While bismuth crystals are rare in nature, you can make large, intricate bismuth crystals at home in your kitchen.

Things You'll Need

Raw bismuth (99.99 percent pure)
Rubber mallet
Old towel
Stainless steel saucepans
Stainless steel fork
Heat source
Stainless steel cookie sheet

Instructions

- 1
  Break up the raw bismuth into nickel-sized pieces by placing the bismuth inside an old towel and hitting it with short, controlled blows with a rubber mallet. Place them into a small but deep stainless steel sauce pan. Cover the bottom of the pan in bismuth pieces, then layer another layer on top of that.
- 2
  Melt the bismuth on your stove over high heat. As it melts, the bismuth forms a greasy-gray layer on top. Gently poke the bismuth with a fork to make sure it is melted all the way through.
- 3
  Set an empty saucepan on a different burner and heat it slowly on high heat. Pour the melted bismuth from its current pan into the new pan; gently push the gray layer away from the edge of the pan with a fork so the bismuth can flow out from under the gray layer. Let this layer cool in the bottom of the pan and discard it.
- 4
  Allow the bismuth to crystallize and harden on a warm burner. The burner should be off so that it cools at an even rate with the bismuth. Let the bismuth harden for about five hours.
- 5
  Gently tilt your saucepan and pour excess liquid bismuth into the first stainless steel saucepan. This frees the crystals, allowing you to see their shapes. Turn the crystals out on a stainless steel cookie sheet when cool to the touch.

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