Make Bismuth Crystals in the Kitchen

Intro: Make Bismuth Crystals in the Kitchen

Bismuth is non-toxic, at least, it is not bio accumulative so you would need to consume a whole lot at one time to have issue. The bismuth compound bismuth subsalicylate is the active ingredient in Pepto Bismol. It is the most highly diamagnetic element known, and is slightly radioactive with a half life of approximately 19,000,000,000,000,000,000 years. The low melting point of 520 degrees fahrenheit makes it a simple task to melt on a kitchen stove.

In case the video does not play for you (I know Instructables has issues playing embedded videos on mobile) the process I use is quite simple:

1. Melt the bismuth in a stainless steel sauce pan. The smaller the pan the better because it will give you a deeper pool of bismuth for the crystals to grow in.

2. Once molten, turn off the heat and skim the oxide and contaminant layer off the surface with a fork.

3. Wait for the surface to begin to solidify, crystals will be forming below as this happens.

4. Gently move the solid rafts that have formed on the surface to keep the crystals on the underside from freezing to the bottom of the pan.

5. When the rafts start to hit other things below the surface as you move them it's time to pull them out and see the result.

6. The crystals formed can be remelted to form new crystals by repeating the process over again if the results weren't satisfactory the first time around.

For best results I recommend using at least 4 or 5 pounds of bismuth for the surface crystallization method demonstrated in the above video. The deeper the pool of bismuth is in the pan the better, because the crystals will have extra room to grow before they touch the bottom. The more you use the more impressive your results will be.

Some of you that are familiar with other forms of crystal formation may be thinking that I give bad advice when I state that you can move the crystals as they grow. Usual crystal growth requires a very still solution with no movement, and a very slow cool down period. I did quite a lot of experimenting with this method and found that bismuth does not behave quite the same way. Once the crystals have begun forming it does not seem to matter if they are moved so long as they remain submerged. Further structured growth happens regardless of disturbance once there is a point to nucleate from.

You may also notice that I was not wearing gloves for a portion of the video, that was foolish of me. I was wearing eye protection the entire time. Leather gloves (not synthetic!) and lab goggles should always be worn in case of splashes or spills.

The bismuth I used for the project was 99.99% pure in ingot form which I purchased from eBay.

Have fun and stay safe!

Comments

[roskellett]

This looks very interesting but not especially useful if the crystals cannot be used to make something afterwards. Perhaps that's a separate project someone has done elsewhere. My big question is regarding the enormous heat of 520 degrees Fahrenheit required - the main part of our oven goes to 550 degrees Fahrenheit, incredibly hot. Well, I guess I will have to try it, after going to a Thrift store to find a "throw awya" pot! THANKS for sharing.

[CricketS3]

Hi. Thank you for a very informative article. Wish I had found your instructable before I bought my little 100 g chunk, didn't realize how much I'd need to do this. Once I get enough, I'd like to do this as a family project with my nieces. If I get 5 lbs, how deep a should the pot be to get the best crystallization? Also, can the crystals be grown on something? (I.E. for making art/jewelry, could I put something either with a much higher melting point for a chain or a non metal material for string) Also, is there anything that can be done with the liquid leftovers?

[NightHawkInLight]

The pot should be as narrow enough that when the bismuth fills it it is about as deep as it is wide. Ideally.

If you are doing this with your nieces it would be best that they watch from a safe distance. This is not a very good kids project since the metal is extremely hot and may splatter if it contacts water. I have not tried growing the crystals on anything, besides the metal sides of the pot.

[jlferrari458]

Just so you know, its pretty much like antimoney or tin-lead alloys. Its not supposedly meant to be digested, but not is physically damageable. Trust me, I would know. I've done it.

[TheScienceNerd1232]

Just wondering how much of 99.99% pure in ingot form (5lbs) will make in terms of grams in actual crystals

[firestar268]

how big of a steel container should i have for 5lbs?

[JoshA11]

This was fun! Crystals made from bismuth bought on ebay. Here's the link:

http://www.ebay.com/itm/100-grams-Bismuth-Metal-99-99-Pure-Element-Crystals-Ingot-Chunk-USA-/251976590733?pt=LH_DefaultDomain_0&hash=item3aaaf9a58d

[smorgsborg]

So freakin cool!

[stephenmack]

So pretty and cool!

[RichardM10]

Nice. Can you give an indication of the time to cool. I'm thinking of doing this with a science group I'm running and I'm wondering if I can to it in an hour long session.

It would also be nice to have a few still images in the instructable.

[NightHawkInLight]

It can easily be done in an hour. Time to cool is about 10 minutes from melting point for a 5 lb quantity. Don't heat the metal any hotter after it is fully liquid, that will increase cooling time.

[RichardM10]

Thanks

[kokoleo]

Mesmerizingly beautiful!

[Garra23]

Do I boil the pepto bismol lol

[lj1vukoder]

Super cool! Great to see another great project from you!