Scientists believe there could be solid diamond iceberg floating on the oceans of Neptune and Uranus, Discovery News said.

Quoting a study published in Nature Physics, the report said that the research, based on diamonds' melting point, found that diamonds behaves like water during exposure to extreme temperature – i.e. freezing and melting – and the surprising revelation led to a new understanding of diamonds and their presence on some of the most distant planets in the solar system.

While diamonds are a relatively common material on Earth, this research was the first to measure their melting point. The process, however, is not as simple as increasing temperature: diamonds are an incredibly hard material, making them innately hard to melt, but the gem is also averse to extremely hot temperatures, which physically change it into graphite.

Subsequently, it is the graphite, and not the diamond, then melts into liquid. The trick for the scientists was to heat the diamond up while simultaneously stopping it from transforming into graphite.

Melting diamonds also requires a high pressure environment: Neptune and Uranus are two planets where ultrahigh pressure and ultrahigh temperatures coexist.

According to the report, the scientists were able to mimic the planets' atmospheres. They then took a small, natural, clear diamond – weighing about a tenth of a carat and half a millimeter thick in size – and blasted it with lasers at ultrahigh pressures. The diamond liquefied at pressures 40 million times greater than what a person feels when standing at sea level on Earth.

The scientists liquefied the diamond at pressures 40 million times greater than that of sea level on Earth. They than slowly reduced both temperature and pressure; and when the pressure dropped to about 11 million times the atmospheric pressure and the temperature dropped to about 50,000 degrees, solid diamond clusters began to appear. The chunks then did something unexpected for stones – they floated, leading researchers to the conclusion that it was behaving like water.

The researchers said that the existence of diamond oceans on Neptune and Uranus could help explain the nature of their magnetic fields as well: unlike on Earth, Uranus and Neptune's magnetic poles do not match up with the their geographic poles.

It is believed that carbon makes up about 10% of both planets. A huge ocean of liquid diamond in the right place could deflect or tilt the magnetic field out of alignment with the rotation of the planet.