TORONTO (miningweekly.com) – LSE- and Nasdaq-listed Randgold Resources has increased the indicated mineral resource at its Kibali project in the Democratic Republic of Congo (DRC) by 23%, the company announced on Monday.

In October, Randgold and AngloGold acquired Moto Goldmines, for its 70% stake in the large Moto gold project (since renamed Kibali), and the companies said earlier this month they had reached an agreement with a DRC government-owned company to buy another 20% in the project.

The indicated mineral resource has been increased to 13,93-million ounces, compared with the previous estimate of 11,29-million ounces, Randgold said in a statement.

The figure includes 7,67-million ounces of underground mineral resource, at a grade of 6,08 g/t in the indicated category, which is an increase of 118% over the previous declared underground indicated mineral resource of 3,53-million ounces, at a grade of 5,1 g/t.

However, the total inferred resources at Kibali have almost halved, from 11,23-million to 5,83-million ounces, which Randgold said was partly because some of the inferred resource was upgraded to the indicated category, but also because the company has taken a conservative view of the resources.

The inferred resource grade did increase to 3,55 g/t in the new resource statement, from a previous 3,3 g/t.

Randgold insists that “all resource estimates reflect only those mineral resources for which there is a reasonable prospect for eventual economic extraction,” the company said.

The resource updated incorporated results from infill drilling on the Karagba-Chauffeur-Durba deposit at the project.

CEO Mark Bristow said in a statement that the mineral resource update had underlined the high quality of the Kibali orebody.

“We’re now working on a review of the geological model and expect to continue to update resources and re-estimate reserves as we obtain new results from our ongoing drill programmes and progress our understanding of the geological controls on mineralisation,” he said.

Bristow said last week he expects to present a development plan for the Kibali project in the first quarter of next year.

According to a March 2009 feasibility study, the Moto gold project contained 42,3-million tons of reserves, at 4 g/t of gold, for 5,5-million ounces of gold.

The study was adjusted from an earlier report, to include plans for a high-grade underground mine, in addition to the openpit operation.

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