Diamonds are composed of carbon atoms that have been heated and squeezed deep underground and then pushed toward the Earth’s surface, where they cool. In trying to mimic these conditions, scientists have successfully created synthetic diamonds in a lab. A possible source of carbon turns out to be peanut butter! Place some peanut butter under some extreme pressure, about 1.3 million times that of our atmospheric pressure, and temperatures of 1,000 deg C, and the result is a diamond. The resulting gems, however, are not much to look at. Most peanut butter diamonds are quite small, around the size of a fennel seed, and they are also discoloured, due to impurities in the peanut butter.