I was using Bismuth for its diamagnetic properties, but since I found the pyrolytic carbon I was left with a few pounds of Bismuth . So I decided to use it for another nice property of Bismuth which is its crystallization that builds structures looking like Inca pyramids.
I adapted a process from a middle age alchemist to create my crystals. Be careful that the following process involves heating at high temperatures with molten metal and requires appropriate heating protections, gloves, glasses, clothes, shoes etc. Here is how I do it: I put a few pounds of Bismuth in a pan and melt it completely with a gas torch (the melting point is 271 °C, 520 °F). It is better to have a temperature a bit higher than the melting point that you can detect from the surface rather be in the yellowish color than the bluish colors. I skim any floating dirt to leave the shiny slivery surface and then I pour everything in a bowl that let the metal cool slowly. I use a stainless steel double wall round bowl that initially was used for ice. Then I let the metal cool for about 9 minutes for my 3 pounds until the surface is hard. In parallel I heat the end of an iron rod and after the top surface is hard I used the rod to pierce two hole to reach the molted metal still below the surface. I then immediately take the bowl with isolating handle and protections and empty the remaining liquid metal into the pan. I then let the metal to cool completely, to speed that process you can pour cold water on the bowl and the pan. Then I remove the cold Bismuth from the bowl and then break it with a hammer or use cutters if the holes are big enough. Once the process timing can need adjustment depending on the bowl size.
I then get crystals like these ones
I know some artist that use the crystals to make jewels or glue them on paintings to add effects.