You're listening to the Skeptics Guide to the Universe, your escape to reality.

Hello and welcome to the Skeptic Guide to the Universe.

Today is Thursday, October 23rd, 2025, and this is your host, Stephen Novella.

Joining me this week are Bob Novella.

Hey, everybody.

Kara Santa Maria.

Jay Novella. Hey, guys. And Evan Bernstein. Good afternoon, everyone. Kara, how is your jewelry making course going? Oh my gosh. I love it so much. I'm doing this. It's like bench jewelry. So basically it's a silversmithing class. And I'm learning all sorts of fun skills like when I say soldering soldering in bench jewelry is completely different than the type of soldering that you're used to

doing with electronics it uses like this giant torch with a mix of propane and oxygen depending on if

you're doing using a work flame or a solder flame or an annealing flame. U-Tan, propan. So you're doing it just with heat. You don't have additional solder that you're putting that. No, you do some, you do use additional solder. So fusing is without solder and soldering is with solder. Okay. But you're not using like one of those little kind of soldering pen things that you usually use

with electronics. It's way higher heat. Yeah. And you need more control. And the solder itself.

What's the temperature of the torch? Oh, gosh. I don't know, but it's blue. It's like bright and

intense. Yeah. I've been using a blow torch recently also for a completely different thing.

So I know for a fact that it's 2,100 degrees. Oh, okay, cool. And so... Just a regular blow torch. For a Fahrenheit. Well, the one we use in class is, it's not even a blow torch. I don't know what it is. It's a nozzle that's got these, you know, big cables that are attached to a giant oxygen and giant propane tank. But it is propane.

Yeah.

And so you mix it based on how much heat you need. Oh, that might be hotter. Because I'm using just propane and just air, not separate oxygen. We're using oxygen. Yeah, I wonder if that's hotter then. And it might be that we need it to be cleaner for the silver. I'm not sure. Yeah, and so because sometimes you have to anneal metal to soften it so you can work with it more. Obviously, you need heat to solder. And the soldering chips or wire is silver. So you're

soldering with more silver, but I think it has like a different melting point. You know,

filing, we use a jeweler saw to file, a lot of like dapping and texturing, pickling, like chemistry, all these

calculations. It's really fun. So I made a pair of earrings, which are mixed metal. They've got bronze and

copper and silver. And then I'm working on a ring right now. And the hope is that before we finish

class, we can do a bezel set stone, which uses fine silver.

So that's not 925.

It's actually 100% silver for the bezel.

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