"Diamond is a relatively common material on Earth, but its melting point has never been measured," said J. H. Eggert of Lawrence Livermore National Laboratory in Livermore, Calif. "You can't just raise the temperature and have it melt, you have to also go to high pressures, which makes it very difficult to measure the temperature."
Ordinarily, before diamonds are melted, they turn into graphite. It takes a perfect level of pressure and heat to turn them into liquid diamond form. Researchers found that the pressure has to be similar to those found on Neptune or Uranus.
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