What connects gold and baby hair?
Babies are precious to their parents, but their hair is valuable in a more literal sense.
1. As gold is unreactive, it exists as nanoparticles in seawater and the soil. Plants and animals absorb some of these gold nanoparticles, so they pass up the food chain to us.
2. Even if you don’t have any gold fillings, there is about 2mg of gold in your body. If you could somehow extract this, it would be worth just over 6p.
3. Our bodies carefully regulate the concentrations of biologically active metals such as zinc and copper and remove any surplus via the skin and hair. Gold, though harmless, is excreted the same way.
4. Babies under three months have more gold in their hair than older people. This comes from their mother’s breast milk and can reach double the average concentration of gold in Earth’s crust.
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