The Hypatia stone found in the sahara desert.
The Hypatia stone is believed to come from the nucleus of a comet.
But new analysis by the team of researchers who initially analysed the Hypatia stone threw up unexpected results.
Most meteorites are made of silicon with a small amount of carbon, but the Hypatia stone has a huge amount of carbon compounds – some, known as polyaromatic hydrocarbons, are a major component in interstellar dust.
The stone also contains pure aluminium.