Shares in Stellar Diamonds (LON:STEL) were lifted in opening trade after the group reported a significant maiden resource for the Droujba kimberlite pipe in Guinea.
The JORC compliant study puts the Droujba resource at 2.474 million carats in the inferred category, with a grade of 70 carats per hundred tonnes (cpht).
Together with the maiden resource announced on the high grade Tongo kimberlite dyke project in Sierra Leone, this takes Stellar's initial global resource base to 3.1 million carats.
The news sent Stellar shares rising and by 8.52 am, they were trading up 7 per cent at 7.625 pence.
The company estimates the current in-situ value of the contained diamonds between US$124 and US$192 million.
This maiden resource is defined to a depth of 360 metres below surface and there is additional resource potential from Droujba and other kimberlites in the licence area.
The pipe has been drilled to 414 metres depth and remains open below that level.
The volume of pipe between 160 and 190 metres has not yet been declared a resource and contains an estimated, non-JORC 400,000 carats which requires further delineation drilling.
Resource drilling and bulk sampling of the adjacent 5 kilometre long Katcha Dyke which has a reported grade of approximately 100cpht, is not included in the mineral resource estimate.
Chief Executive Karl Smithson said: "This resource base gives Stellar an excellent platform on which to build and we are currently planning aggressive programmes to increase our resources at Droujba, Tongo and at our Kono kimberlite dyke project where evaluation results for the high-grade Lion-5 kimberlite are expected to be announced in the near future.
"I am pleased to report that in the past twelve months Stellar has achieved all of its key milestones on time and within budget and going forward we have a clear strategy of value enhancement of our assets as we move projects through to the mining feasibility study stage."