I have been reading up on the "s" (slow) process for making elements.<br /><br />It starts with nitrogen 14 fuzing with helium 4 to produce flourine 18. That then emits a postitron and a neutrino to produce the neutron. That then fuzes with helium 4 to produce neon 22, which fuzes with another helium nucleus to produce magnesium 25, liberating the neutron.<br /><br />There are other reactions that produce neutrons, but that's the important one.<br /><br />Neutrons have a half-life of 11 minutes, so the neutrons need to be asorbed in that time frame to produce heaveir elements, which is usually what happens. The starting material is plentiful iron, which is produced in abundance in Type Ia supernovae, the most common.<br /><br />So copper, for instance, is fairly common. But as the elements get heavier, their abundance decreases. As a result, zinc and cadmium are less common than uranium. Silver is 40 times less common than uranium. Platinum, palladium, and rhenium are rare, indeed. The rare-earth elements as a group are fairly common, but each element is fairly rare. They are found in concentrated ores because of their unusual chemistry, with each rare-earth element having a very similar chemistry to the other rare-earth elements. The beach sands of Florida (monazite) are rare-earth elements, and India has similar large deposits, as do other places. Here also you will find thorium and uranium, which are also rare-earth elements as far as their chemistry goes. Rare earth ores are indeed rare in Europe for some reason, which is why they are called rare-earth elements.<br /><br />This has public policy implications:<br /><br />1) If some dictator claims that a competing dictator is buying uranium from a third dictator, then the first dictator is lying. The dictators of South Africa, North Korea, India, and Pakistan all got their uranium from their own countries. This does not apply _only_ to current or recent dictators, but also to future dictators.<br /><br />2) The