DENJIRO: Do you know what this is I have here?
GIRL: Is it some sort of metal?
DENJIRO: This is a metal called “bismuth.” You might’ve never heard of it, but you can see a very interesting phenomenon with it. Bismuth has a low melting point at 271 degrees Celsius. First, let’s melt it with this gas torch.
Once it melts, I’m going to turn the heat off and let it cool. Watch what happens to the surface.
GIRL: There’s a film on the surface!
DENJIRO: Bismuth is a metal that easily bonds with oxygen. When it melts, the surface bonds with oxygen and quickly forms an oxide film. Now, watch what happens when I remove this film with a fork.
GIRL: The color’s changing!
DENJIRO: The surface is a different color now. The color actually changes depending on the film’s thickness. Since the thickness varies each time, the color changes whenever you remove it with a fork. If you wait a while after melting bismuth, it starts to harden on the inside. Let’s see what it looks like. I’m going to pour out the melted bismuth. Let’s see what’s inside.
GIRL: That’s so pretty! It looks like someone made that!
DENJIRO: They look like manmade objects, but these are actually bismuth crystals. They’re known as hopper crystals and have geometric shapes.
NARRATOR: Bismuth is being used for superconductor experiments for the maglev train line.
DENJIRO: I hope energy will bring you all happiness. Our magic word is "Happy Energy!”
Негізгі бет A Most Mysterious Metal: Bismuth (Mr. Denjiro’s Happy Energy!
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