Pink diamonds, renowned for their rarity and high value, have long baffled researchers due to their unique coloration compared to colourless diamonds. However, a team of Australian researchers has finally unravelled the mystery behind these precious gems.
According to a study published in the journal Nature Communications, pink diamonds emerged on the Earth’s surface approximately 1.3 billion years ago during the breakup of one of the planet’s earliest supercontinents, Nuna. This groundbreaking research suggests that there may be more of these colourful gems hidden in ancient continental junctures.
PINK DIAMONDS; CONTINENTAL BREAKUP
Lead study author Dr. Hugo Olierook, a research fellow at Curtin University’s John de Laeter Centre in Perth, Australia, explained that the area where the Argyle mine, responsible for more than 90% of Earth’s pink diamonds, is located, experienced stretching during the continental breakup. These stretching created gaps in the Earth’s crust, allowing magma to rise to the surface, bringing with it the pink diamonds.
Typically, diamonds are found in the middle of ancient continents, within volcanic rocks that rapidly transport them from deep within the Earth to the surface. However, these gems form under unique conditions, subjected to intense forces resulting from the collision of tectonic plates, which twist and bend their crystal lattices. This process is responsible for the hue in these diamonds, as well as in most brown diamonds.
In the case of Argyle, the pink diamonds formed approximately 1.8 billion years ago during the collision of Western Australia and Northern Australia, deep beneath the Earth’s crust. As a result, once-colourless diamonds turned pink hundreds of miles below the surface.
UNDISCOVERED GEMS
The study also suggests that there may be undiscovered such stones -bearing volcanoes, potentially including some in Australia, given that the edges of ancient continents where these diamonds form are often covered by sand and soil. The unravelling of this geological mystery sheds light on the origins of these highly prized gemstones and could open the door to the discovery of more such presciiopus gems in the future.