How old are diamonds? 

Most natural diamonds are between 1 and 3 billion years old. Diamonds form deep within the Earth under intensely high temperatures and pressure, causing carbon atoms to crystallize before being transported to the Earth’s surface by powerful volcanic eruptions, such as kimberlite and lamproite eruptions. Although diamond formation occurs far beneath the Earth’s surface, these eruptions are rare yet immensely powerful, carrying diamonds from the Earth’s mantle to locations where they can be recovered.

These rare and precious gemstones are likely the oldest things you will ever touch, having formed long before any life existed on Earth. The oldest diamonds that have been dated, found in Canada, are 3.7 billion years old.