The Fascinating Science Behind Pink Diamonds: An Inside Look at the Argyle Mine’s Closure and its Legacy in the Gem Market

Pink diamonds, known for their rarity and high value, have captured the attention of collectors and gem enthusiasts worldwide. The Argyle mine in Western Australia was responsible for producing over 865 million carats (172 tonnes) of rough diamonds, including 90% of the world’s pink diamonds. However, the mine closed in 2020 due to a decline in diamond supplies and unfavorable economic conditions.

Pink diamonds are unique because they get their color not from impurities like blue and yellow diamonds but from geological processes that deform the crystal structure. This makes them highly sought after by collectors and jewelers alike.

The Argyle Formation, where these precious gems were found, is located on the edge of a continent and is made of olivine lamproite rock instead of traditional kimberlite formations. Researchers have determined that this formation is around 1.3 billion years old, shedding light on the conditions under which pink diamonds are formed.

The creation of pink diamonds occurs when tectonic plates collide under intense pressure and temperature conditions, causing pre-existing diamonds to take on different pink tones. This process occurred as the Nuna supercontinent began to break apart 1.8 billion years ago, creating perfect conditions for pink diamonds to form in the Argyle Formation.

Rio Tinto, the company that owned and operated the Argyle mine, was able to extract a large quantity of brown diamonds from the area in addition to the highly sought-after pink diamonds. As demand for pink diamonds continues to grow, experts predict that future mines will need to be designed specifically with pink diamond production in mind.

In conclusion, pink diamonds are not only valuable but also unique due to their formation process and rarity. The closure of The Argyle Mine has left many collectors feeling nostalgic about this iconic diamond producer’s contribution to the gem market.