Most of us might think that the world's colour is black or dark grey. However, scientists have found out that pink is the oldest known colour. Researchers looked at 1.1-billion-year-old rocks beneath the Sahara Desert. They crushed the rocks into and found the bright pink colouring in them. This means that pink is the oldest colour on geological . Dr. Nur Gueneli from the Australia National University led the . She made the discovery in a in Australia. Dr. Gueneli said the colour was produced by organisms that lived in the oceans. She added that the are so old they no longer exist. At that time, tiny organisms were the largest life on Earth.
Dr. Gueneli said her first was "sheer amazement". She said her team thought the rock powder might turn black when they were doing their on it. Instead, it turned pink. Another said: "I remember I heard this screaming in the lab. Dr. Gueneli came running into my and said, 'look at this,' and she had this bright pink stuff…It turned out to be colour, 1.1 billion years old." The rocks could contain other colours, from a red to a deep purple. Gueneli explained how her find was. She said: "Imagine you could find a fossilized dinosaur that still has its colour - green or blue. That is exactly the of discovery that we've made."