Bismuth crystals are surprisingly easy to make in the classroom or laboratory setting. All that is required is a hot plate, 2 containers (one to melt the metal and one to pour into), and some pure (99.99%) bismuth metal.

Materials:
1.  Hot plate, bunsen burner, or propane torch

2.  Two containers or crucibles. One will be used to melt the bismuth in, the other to pour some of the melted liquid into.  Bismuth melts at 271.40°C (520.52°F), so small iron or steel pots will work well for this.  I usually use steel measuring cups, steel cans, or porcelain crucibles.  I have used ceramic mortars and evaporating dishes before (as in photos), but these break easily after multiple uses (especially the mortars).  If a class lab is being conduced, an economical alternative to crucibles is to use the bottom end of a soda pop can for the casting.

3. Heat resistant gloves I just use regular old work gloves. buy them cheap at Home Depot, Lowes, Wal Mart, etc. 
 
4. Bismuth metal.  This can be purchased from a variety of Internet sources, including EBay. I routinely purchase my  

Procedure:
1.  Place a small amount (about 1/4 lb) of the bismuth metal into one of the containers.  Place the container on a hot plate and heat until fully melted. You can also use a torch or a Bunsen burner to melt the metal.  Melt it slowly so that it remains at a relatively low temperature - in other words, don't leave it on the hot plate or burner any longer than is necessary.

2.  Remove the container from heat and allow to cool until approximately 50% of the sample is solidified.  This is the tricky part, as the container needs to sit undisturbed during this

bismuth at http://rotometals.com, as the price is reasonable (about $14.00/lb), and the quality is excellent (photo, right). You want very pure metal, so be sure that when you order it it is at least 99.99% pure.  Order quantities based on your project, of course.  One pound would be enough if you are not too sure about the project, or want to try it on a small scale.  Each time you melt the bismuth, an oxide layer forms along the top and is lost as "slag".  So factor this loss in in your calculations.
cooling time.  It will begin to solidify around the bottom and sides first, with some amount of "skin" solidifying on the top.  I occassionally check the solidification process by ever-so-slightly moving the container to see how much is still liquid. When about half of it has solidified, pour off the rest of the liquid into another container.  What you will be left with is a solidified coating of bismuth in the container with crystals where the solid-liquid interface was. You want to do the pour very rapidly, so that the crystals underneath do not catch a bunch of the slag floating on top.  The proper technique may take some time to learn, but soon enough you should see some beautiful crystals on the bottom of the container.

Student Laboratory Procedure:
1.  Using an ordinary aluminum soda pop can, tear the punch tab off of the can so that the can will rest flat on the top when inverted, exposing the concave well in the bottom of the can. This depression will be used to cast the bismuth crystals.

2.  Place a small amount of bismuth onto a steel ladel, large steel spoon, or small crucible.  Use a hot plate or bunsen burner to melt the metal (photo on right shows a steel spoon being heated over an ordinary kitchen gas burner). Melt it slowly, trying not to heat the metal any more than required to melt it.

Student Laboratory Procedure:

3.  Pour the liquid metal from the spoon into the can depression, filling it to the brim.

4.  Allow the metal to cool until the bottom half is solid.  Then gently pour off the liquid from the top.  There will be a ring of small bismuth crystals remaining in the can.

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