An experiment replicating early conditions on Mercury, the smallest planet in the solar system, suggests that a thick layer of diamonds may be hiding hundreds of kilometres beneath its surface.
We already know that Mercury has plenty of carbon, the building block of diamonds, because observations by NASA’s MESSENGER spacecraft found that its surface is covered in graphite. This carbon may be spread throughout Mercury’s interior, with its exact form depending on the temperature and pressure in each location. …
Source: www.newscientist.com