Transcription
I'm trying to grow crystals of ruby at home, and in the last episode, I reached the limits of what I could do without proper platinum crucibles. So, I ordered a shiny new one, and then I found a deal on this beat-up used one, too. This was pretty expensive, but I'm all in on this project, and it'll double the speed. So, let's get them cooking.
First up is a test run with the usual malibdum oxide, aluminina, chromia, and a bit of sodium carbonate. One crucible got 5 g of the ruby mix, and the other one got 10 g. And 4 days later, let's see what we've got. The 10 g run looks crazy. I guess the concentration was too high, and it only formed micro crystals. But the 5 g run is much more promising. There's still only up to 2 mm, but the quality is way higher and more uniform than before. And best of all, after a soak and water, the mix just comes out of the crucible and it's ready for another run. That went great, so it's time to start the real experiments.
First, I'm going to try lithium malibdate as a flux in one crucible. And I'm going to pre-melt the fluxes to let me fit more in. The normal flux formed a nice flat sheet, but the lithium malibdate pulled together into a sparkly disco ball. Kind of weird. I'm also putting the max temperature higher since the crucible can handle it. So, let's see what we've got. The lithium olive date didn't grow any rubies at all, but it also didn't evaporate off much, so it's still promising as a mix-in ingredient. But the normal flux loved the higher temperatures my old crucibles couldn't handle. Look at these rubies. We're now up to 2.5 mm with way more of the bigger ones, all clear with brilliant crystal faces. But we're still a long ways off from the 10 mm I'd really like to cut them into gems.
And I read about two other additives to the flux. Sodium and tungsten in one set and lithium carbonate in the other. They didn't give ratios, though, so I'm just going to try a random guess and we'll see what happens. The lithium carbonate mix is kind of boring, but the tungsten flux made its own gorgeous crystals. But we're trying to grow rubies here, so let's get them cooking. And after another 4 days, oh, this wasn't that big before, was it? Yeah, it seems like the lithium carbonate mix expanded a bunch as it cooled and bulged out the walls of the crucible. Fortunately, it didn't break, but that could have been really bad for me. The tungsten mix still looks cool, but neither of them ended up having any rubies in them.
So, I decided to retry both of them, just with a lot less of the additives mixed in. And this time, something amazing happened. Both of them had big, beautiful rubies. The lithium run brings the record up to 3 mm with gorgeous pink red crystals that are less platey and better shaped, but the tungsten run was crazy. There were even larger crystals hiding under the surface, bringing the final record for this episode up to 4.4 mm, and they look totally different from the others. They formed sharp double pyramids, what sapphire miners call a dog tooth, and each stone has a dark core with a light pink rind. I'll be honest, I have no idea why that happened. A lot of times, crystal growing is more like alchemy than chemistry. They're still not perfect, but I'm really optimistic about what future experiments could do. And even though I haven't hit gemsized crystals yet, these are big enough to be neat. So, I put a few of them up for sale on the site. They're still very tiny, but if that sounds interesting, you can go to gemsofcience.com to get yours. And stay tuned. As I was editing this, another run ended with some even crazier results you can see in the next episode.