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Has anyone tried doing this with Bismuth? Bismuth crystals can also be grown at low temperature, so maybe they can be shape controlled as well.
I thought these crystals are 3D printed at first judging by the layered look.
> But I did find a study published in the World Salt Symposium where researchers successfully grew pyramid salt from waste salt water in large, steel crystallizers. Wow, I never knew that there was an entire symposium dedicated to salt . From https://www.bolton-menk.com/salt-symposium/ : This event celebrates the optimization of salt use to improve community sustainability and protect vital freshwater systems and inf…
Also 484 pages of the pretty dense but readable, Salt by Mark Kurlansky
Does anyone know of scientific article where I can read more about this? I've never heard of alum's water calming abilities.
> But I did find a study published in the World Salt Symposium where researchers successfully grew pyramid salt from waste salt water in large, steel crystallizers. Wow, I never knew that there was an entire symposium dedicated to salt . From https://www.bolton-menk.com/salt-symposium/ : This event celebrates the optimization of salt use to improve community sustainability and protect vital freshwater systems and inf…
Another recent salt submission: https://news.ycombinator.com/item?id=37786245
> The key is to add an ingredient called potassium alum. Alum calms the surface and helps the pyramids form. Does anyone know of scientific article where I can read more about this? I've never heard of alum's water calming abilities.
> In water, most of the particles are negative charged, to neutralize the charge a positive ion (cation) may be used as a coagulant. Potassium hydroxide contributes a mono-valent ion, K+. Calcium hydroxide gives a divalent ion, Ca2+. Aluminum coagulants give trivalent aluminum ions, Al3+. According to Schultz in 1882 and Hardy in 1900, higher the charge of cation, more effective is charge neutralization.
This charge would be present at the surface[2] if not dealt with via the alum, and I imagine that could disrupt the crystallization process happening there.
[1] https://link.springer.com/article/10.1007/s13201-018-0662-5 [2] https://en.m.wikipedia.org/wiki/Surface_charge
Has anyone tried doing this with Bismuth? Bismuth crystals can also be grown at low temperature, so maybe they can be shape controlled as well.
I think the surface of the melt will oxidize so you might need to cover it with inert gas but something like this might be possible. One issue is that the crystals might want to melt if they grow downwards into the molten liquid. I think the temperature gradients might be really important here.
Hm, I'm trying to think of ways to maintain an even gradient without unduly stirring up the liquid metal.
Probably sealing the pot-o-bismuth inside another container, where the outer container's fluid is being stirred and circulated to minimize external gradients.
This website is what I want the internet to be. Information like this is such a treat, and I would have gone crazy for it as a kid (and I still do). I used to search high and low for books containing these kinds of guides, and it makes me happy to see it online.
I've got alum on order. My kid isn't old enough to do this one unsupervised, but this is our plan for next weekend.