Gemfields (LON:GEM) shares were lifted as the importance of its Montepuez deposit in Mozambique was underlined - with the discovery of what the miner called an "exceptionally rare" pair of matching rubies.
It follows the unearthing of the 40 carat ‘Rhino Ruby’ last year at the 340 sq km Montepuez deposit.
Gemfields also noted in today's announcement that several labs have confirmed that certain Mozambican rubies display the legendary “pigeon blood” colour, which was previously found only in stones from Burma.
The latest matching pair of rubies have a combined weight of 45 carats, and they will be a highlight at next week' ruby auction in Singapore.
Last month a 25.59 carat Burmese ruby with such a pigeon blood colour reportedly sold in Geneva for a record £19million.
Ian Harebottle, chief executive (CEO) of Gemfields, said: "It is extremely rare to find two matching rubies of this size, colour and quality.
"Their discovery underscores the importance of the Montepuez deposit as a source of some of the highest quality rubies the world has seen in generations.
"If this remarkable matching pair was to make it to the Paris Biennale in 2016 they would simply steal the show!”
Speaking to Proactive Investors, he added: "I have spoken to 10 or 20 of the world's leading coloured stones experts and none of them have ever seen them in their lives so hopefully that puts in in perspective.
The company boss said it would be a "travesty" to take them apart and that the aim would be to sell them as a pair.
He said the potential value of the stones in the hands of the right jeweller or collector was "kind of priceless".
Gemfields shares added 1.67% to 61p each.