A glittering treasure has been found in Botswana, and it’s causing quite a stir. A half-pink, half-colourless rough diamond weighing 37.41 carats, that’s around 7.5 grams, was reportedly uncovered at the Karowe Mine, as reported by the BBC. The stone is about an inch long and shows a striking split between the dusty pink and transparent halves. According to the experts, these finds are extremely rare and can only form under the right conditions, deep beneath the Earth’s crust, where heat and pressure push carbon atoms together. This one apparently started life over three billion years ago, far down, hundreds of kilometres below the surface. It seems almost unbelievable that it made its way to us.

How this rare bi-coloured diamond stands out in Botswana

Diamonds get their colour in funny ways. Some pick it up from impurities, others from distortions in their structure. Pink diamonds are especially interesting. Scientists say the pink section of this diamond formed first, and the clear part came later. Too much distortion can turn a diamond brown, so hitting the right balance is rare. Experts appear excited because this one is big and bi-coloured, which makes it unusual. Most pink diamonds they see are tiny. This half-pink diamond seems special, where some experts say it could become one of the most important pink diamonds ever polished. Oded Mansori, co-founder of diamond cutting firm HB Antwerp, apparently believes their process can capture the colour at its best. It might end up looking astonishing once cut and polished.

Why do people feel fascinated after the discovery

Part of the fascination is how old the diamond is. Over three billion years down there, under intense heat and pressure. It travelled all that way through volcanic eruptions to reach the surface. That journey alone is mind-boggling. And then there’s the colour. Only about four per cent of pink diamonds have the kind of vibrancy seen here. Experts say it’s graded “internally flawless,” which in diamond terms is about as perfect as it gets.