Nuclear power plant.

Image Source: Getty Images.

If you haven't noticed, North Korea seems set on building a nuclear bomb capable of reaching Japan -- or further. Iran also has "nuclear capable" on its to-do list. Even U.S. President Donald Trump is talking up the value of nuclear weapons. It's all kind of scary, but there's so much more to "nuclear power" than just bombs. And a deeper look at uranium is exactly what you need to understand that nuclear isn't all bad. Here are eight facts I bet you didn't know about nuclear fuel uranium.  

A core sample at a uranium mining site.

A core sample at a Cameco mine. Image source: Cameco Corp.  

1. More common than you realize

The aura surrounding uranium -- that it's difficult to obtain -- would make you think that it's a pretty rare element. But that's just not true. For example, it's 500 times more common than gold. You can find it as easily as you can find tin. In fact, there are even traces of uranium in granite (4 parts per million), which makes up 60% of the Earth's crust. In other words, uranium is pretty much all around us.  

Don't worry, though, you aren't at risk of radiation poisoning. That's because uranium is concentrated enough to cause trouble in just a few spots. And those would be the ones where miners set up shop to pull the nuclear element from the ground.  

A Cameco employee working in the Cigar Lake uranium mine.

A Cameco employee working in the Cigar Lake uranium mine. Image source: Cameco Corp.   

2. You need a lot of it

Although uranium is more common than you may realize, it only makes economic sense to mine it from places where there's a lot of it. In fact, according to the World Nuclear Association, uranium is only slightly radioactive. Only about 0.7% of uranium is what's known as "fissile," or capable of undergoing fission (that's the process that unleashes the awesome power held within uranium).

As an example of how much uranium is actually needed every year, Cameco Corp (CCJ -1.45%), the world's largest publicly traded uranium miner, sold 31.5 million pounds of the stuff in 2016. And that was down from 32.4 million pounds in 2015! That's a lot of uranium.  

A Cameco employee working at a uranium processing facility.

A Cameco Employee at a processing site. Image source: Cameco Corp.

3. All uranium isn't created equal

So only a small amount of uranium is actually capable of fission. That's because uranium comes in different main forms, uranium-235 (U-235) and uranium-238 (U-238). It's kind of complicated, but the gist is that the type of uranium used in nuclear reactors is uranium-235, and in order for it to be useful, it needs to be in concentrations of at least 3.5% to 5%. To get it up from its 0.7% natural concentration, uranium has to be enriched.  

That requires uranium to be turned into a gas so that U-235 can be concentrated relative to U-238. That process involves centrifuges that spin the gas and take advantage of the 1% mass difference between the two varieties of uranium (also called isotopes) to separate them. Weapons-grade uranium, in case you were wondering, is upward of 20% U-235. (The bomb dropped on Hiroshima was 80% enriched uranium.) The U-238 that's separated out is known as depleted uranium.  

A pile of unused bullets.

Uranium is found in more than just nuclear weapons -- it's also found on the tips of some bullets. Image Source: Getty Images.

4. Weapons-grade depleted uranium?

We all know that uranium can be used to create nuclear bombs. But what you might not know is that depleted uranium is used in armor-piercing bullets! (And in larger projectiles as well.) This has nothing to do with uranium's radioactivity, but everything to do with mass. Mass is basically how much matter is in an object. For example, a 1-square-inch block of balsa wood weighs less than an inch-square block of lead -- lead has more mass. And depleted uranium is roughly 70% denser than lead! Orbital ATK (OA), for example, makes use of depleted uranium in some of its munitions.  

Once again it's kind of complicated, but the density of depleted uranium allows it to more easily break through protective armor. What makes it a good choice for armor-piercing munitions (sometimes called kinetic energy penetrators) also has to do with projectile shape involved and what happens when uranium's temperature increases and pressure is applied. But suffice it to say, uranium finds its way into more weapons than just nuclear bombs.  

A General Dynamics tank.

A General Dynamics tank. Image source: General Dynamics.

5. A little protection

The interesting thing here is that depleted uranium, because of its density, can also be used to create protective armor for things like tanks. Since the science behind enriching uranium is pretty complex, "making" depleted uranium, which is actually considered the waste product of enrichment, is more difficult than you might think. In other words, not everyone has the ability to make armor-piercing bullets (let alone afford them). So having a highly dense protective shell made with depleted uranium can save lives when regular munitions, or more powerful ones, are involved. General Dynamics' (GD 0.07%) Abrams tanks are just one example of depleted uranium showing up in armor.  

But that's not all the protection depleted uranium affords. For example, because it is so dense, it is used as a shield against, somewhat ironically, radiation in the medical and industrial spaces. It's also used in protective containers for, you guessed it, radioactive materials. And you thought being "dense" was a bad thing!  

A modern Boeing 747 in flight.

A modern Boeing 747. Image Source: Getty Images.

6. Do the locomotion

The density of depleted uranium makes it useful for other applications, too. For example, the Pen Duick VI, a racing boat, was controversial because it used depleted uranium in its keel. The benefit of this over a more typical keel with lead in it is that the keel could be thinner for a given amount of weight (density at work again).  

This small-and-heavy factor is essentially the reason that airplane makers used depleted uranium in their trim weights. In fact, Boeing (BA 0.19%) built its iconic 747 with depleted uranium weights between 1968 and 1981. After that point, the global airplane manufacturer switched to tungsten weights and provided airplane owners replacements for the uranium ones. (Though the company has no idea if those replacements were actually used or not...)  

A nuclear power plant on a clear day.

Dukovany nuclear power plant. Image Source: Getty Images.

7. Back to power

But let's be honest, the main use of uranium is for power, which is the market that giant uranium miner Cameco sells millions of pounds of uranium into. According to the World Nuclear Association, "Typically, some 44 million kilowatt-hours of electricity are produced from one tonne of natural uranium. The production of this amount of electrical power from fossil fuels would require the burning of over 20,000 tonnes of black coal or 8.5 million cubic metres of gas."  

It's little wonder, then, that China, with its well-publicized environmental issues, has around 21 nuclear reactors under construction today. The country is already generating 35 gigawatts of power from nuclear plants, with the goal of increasing its power output to 58 gigawatts by 2020 (the 21 reactors under construction are expected to produce 23 gigawatts of power). India, meanwhile, has 22 reactors running, with five under construction. Cameco, by the way, sells uranium to China and inked its first uranium-supply deal with India in 2015.  

All of that said, these aren't the only countries building new nuclear power plants. There are a total of 58 plants under construction today. Although uranium prices are historically low right now, industry participants expect demand and pricing to pick up once all the new construction is done.

A diagram of a pressurized heavy water reactor.

An example of one type of nuclear reactor. Image source: World Nuclear Association.

8. Reliable "clean" energy

When nuclear power makes headlines, it's usually because of a major disaster. A recent example is the Fukushima meltdown in Japan, an event that led to the entire shutdown of Japan's nuclear fleet. Japan has since realized that it needs to include nuclear power in its grid and has started the slow process of restarting its plants. But the bigger takeaway here is that nuclear power is a lot like air transportation: You hear about the airplane crashes, but not about the millions of flights that have gone off without a hitch.  

Nuclear energy, in fact, is really quite safe and reliable the vast majority of the time. In fact, it doesn't produce carbon, leading some to consider it a clean fuel source. Which is actually quite good for solar and wind. Why? According to the U.S. Energy Information Administration, nuclear power plants were hitting capacity factors of 92% in 2016. That means the U.S. nuclear fleet produced 92% of the energy that it was capable of producing last year. Capacity factors for wind and solar were 35% or less.

This isn't to suggest that nuclear is better than solar or wind. Only that nuclear provides a reliable complement to these highly variable power sources, which is why even some environmental groups have started to support, or at least not oppose, nuclear power.  

More than bombs

Sure, uranium can be put to work in a destructive way. That includes bombs and armor-piercing munitions. But uranium is far more complex. It's actually quite hard to effectively mine and weaponize, for example, which is why Iran and North Korea have had such a difficult time making capable bombs out of the stuff. And then there are the more desirable uses of enriched uranium, for things like generating power, and depleted uranium, for protective armor and as a shield against radiation.

If you can see past the negative sentiment, you might find that the uranium sector deserves a second chance. For example, uranium miner Cameco sells a fuel that powers the world's nuclear generators. In China and India that's helping to lift people out of poverty in an environmentally friendly way. That makes uranium look pretty good in my book.