On other planets, it rains diamonds. Nature writes:
It may actually be raining diamonds on Saturn and Jupiter, according to two planetary scientists.
In their scenario, lightning zaps molecules of methane in the upper atmospheres of Saturn and Jupiter, liberating carbon atoms. As the soot particles slowly float down through ever-denser layers of gaseous and liquid hydrogen, it is compressed into graphite, and then into solid diamonds before reaching a temperature of about 8,000 °C, when the diamond melts, forming liquid diamond raindrops. Saturn may harbor about 10 million tonnes of diamond produced this way.
“If you had a robot there, it would sit there and collect diamonds raining down,” Baines says. In their vision of the year 2469, diamonds would be collected on Saturn and used to make the ultra-strong hulls of mining ships delving deep into the planet’s interior to collect helium-3 for clean-burning fusion fuel.