The Earth itself is around 4.65 billion years old, so not much older than black diamonds. Carbonados are extremely rare and have only ever been discovered in Brazil and the Central African Republic.

A billion-year-old black diamond, believed to be the world's largest cut diamond, has sold for £3.16m ($4.3m).Black diamonds ...

Only known to exist in Brazil and the Central African Republic, “carbonado” black diamonds date from around 2.6 to 3.8 billion years ago and are an extremely rare natural occurrence.

Instead of being red or green, the skin is jet black. Black Diamond apples (Malus Domestica) are a rare variety of Chinese ...