Tchegi is one of two sites deemed to be viable by the company in the Lunda North province and situated about 850km east of the capital city of Luanda.

Escom president Helder Bataglia told Bloomberg that the site, along with Escom’s existing Luo kimberlite mine, will produce 35,000 carats a month by the end of 2013.

"By next year we hope to arrive at normal production in Tchegi. Our aim is kimberlite mining where the stones are heavier, but we have alluvial projects because the quality in that area is very good," said Bataglia

BHP Billiton and Escom have invested $200m over the past eight years to prospect 14 concessions in the region, Bataglia added.

Escom and state diamond company Endiama also plan to evaluate three new kimberlites and expand mining at the $300m Luo site with a feasibility study expected by March 2014.