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He's offered to show me how the atoms in our bronze stack up, literally. David tells me that when we reach full magnification, we will have images of the actual atoms in the bronze, something few people have ever seen. Zooming in a hundred million times would allow me to pick out, not just a car, but a bug, crawling in the grass next to it. And the brighter colors are things that contain more tin, and the things with less tin are the things that are slightly darker. The microscopic structure of metals is not uniform. Boundaries between grains are actually defects in the orderly arrangement of the atoms. We only have to shake things by an atom for the image to vanish. The actual bronze chip itself is about a hundredth the thickness of a human hair.I brought you a couple of hunks of bronze, uh, one of which was knocked off of a bell when it was done and one of which is un-poured. I need an area about the size of a farm, and you've given me the whole of the United States. It's too small for us to see, so we have to mount it on a carrier grid, so we can handle it. Like, like, for one thing, I notice they're really, really grid-like.To see what it takes to get something bigger than that tiny bead, I visit the processing plant where the ore ends up. Here too, extraction begins with crushing, in these huge tumblers. So what the farmers would do is they would say, for example, "David, you loan me some money, okay? I can hardly think of anything that doesn't have either a tiny bit of copper or lots of copper. When placed in a circuit, the negatively charged particles line up and flow as an electric current.And that sets the stage for the trickiest step, coaxing the microscopic gold out of the rocky ore. And then, in the future, I will sell you that crop that I planted for this amount of dollar." So what I'm doing is I'm selling you the right to buy or sell my future crops. The sea of electrons also creates flexible, metallic bonds among the atoms.
One proton is hydrogen; two protons, helium; three protons, lithium; four protons, beryllium; all the way up to element 118, with 118 protons. But, I have to say, I've never completely gotten it right. And if you think about it, the name of each element is the least important piece of information you could possibly have.I wonder, though, if there's a more scientific way to evaluate the metal. First, a polishing wheel gives the bronze a mirror-like finish. We'll have to zoom in a hundred million times to see an atom.To find out, I'm taking a piece of it to David Muller, at Cornell University. Then the sample is inserted into a powerful electron microscope. To understand the scale, imagine if I were floating in space, 2,000 miles above the earth, looking down at the United States. Now what we're actually starting to see is the microstructure of the grains in that bronze. They are meant to absorb and reflect sound, because the microscope itself is so sensitive that if you were to talk, just the pressure wave from your voice is going to, is going to give enough mechanical vibration to shake this thing around.The number of protons is called the atomic number and it's the fundamental organizing principle of every table of the elements, including this one. They're filled with stats and figures that don't make any sense to the ordinary person. What matters about elements is that they are real physical substances with properties and things you can do with them. I have to say many of these elements look the way you would think—gold looks like gold, silver looks like silver—but not all of them.Theo makes the point by putting me in touch with the real deal. To make the entire table less abstract, he invites me to lay out the rest of his collection of pure elements. This is a visual representation of every single element that makes up this entire planet and everything on it. As we can clearly see, more than 70 percent of the elements on the table are metals, shiny, malleable materials that conduct electricity. Everything from here on over, including the bottom part, is all metals. And down the middle are these, kind of, halfway in between things, which include, for example, semiconductors, like silicon. The one I was looking at, in particular, was calcium. This is when Theo's collection starts to get really interesting, when he pairs the pure elements with their more familiar forms.
Where do nature's building blocks, called the elements, come from? Her job is to figure out how much gold is in them there rocks. I don't see any more rocks in here, but the bad news is, I don't see any gold in here, either. Final steps: cool and clean the bars, stamp them with their unique serial numbers and their weights. The ancients first learned how to heat rocks to extract copper, at least 7,000 years ago. Traders in New York, London and Shanghai buy and sell more than 20 million tons a year. Copper has been prized for millennia for its unique properties: it conducts electricity better than any metal except silver; it's malleable and has a moderate melting temperature; it even scares away bacteria. Even with all the other modern materials available, they still choose bronze. Hasn't something better come along, after all these years? The quality of the sound depends on the atomic structure of the material.