The type IIa rough has been dubbed the Lulo Rose and is believed to be the largest pink diamond discovered in the past three centuries.
Stephen Wetherall, Lucapa managing director, released a statement declaring the discovery to be a moment in history.
“Lulo is an exceptional alluvial resource and is truly a gift," he said.
"We are once again made very proud by yet another historic recovery.
"We too look forward to our partnership progressing its exploration effort, where we are now bulk sampling the priority kimberlites, in search for the primary kimberlite sources of these exceptional and high-value diamonds."
Angola’s Lulo mine has been a happy hunting ground in recent years for mining companies, with the Lulo Rose the 27th diamond extracted in excess of 100 carats since commercial production began in 2015.
The largest diamond ever discovered in Angola – the 404-carat 4th February Stone – was discovered in the Lulo mine in 2016.
Lucapa has revealed plans to sell the diamond through an international tender conducted by Angola’s state-run diamond marketing company Sodiam.
The company has a 40 per cent stake in the Lulo mine. The remaining equity is held by Angola’s national diamond company (Endiama) and Rosas & Petalas, a private company.
History in the making?
Pink diamonds continue to be the world’s most highly sought fancy colour diamonds and the Lulo Rose may belong to an elite class.
The Darya-i-Noor is the largest pink diamond, polished at 186 carats and originating from the Kollur Mine in India. The diamond is currently part of the Iranian crown jewels in Tehran.
At 59.6-carats, The Pink Star shattered auction records when it was sold for $US71.2 million ($AU101.79) at Sotheby’s in 2017.
Many other pink diamonds have produced staggering results at auction. The 34.65-carat Princie Diamond fetched $US39.3 million while 24.78-carat Graff Pink was sold for $US46.2 million.
Other notable pink diamonds include the Sweet Josephine (16 carats) which was sold for $US28.5 million and the Spirit of the Rose (14.83 carats) which sold for $US26.6 million.
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