Botswana Diamonds (LON:BOD) is planning a bulk sampling programme in Cameroon after it was awarded a 430 square kilometre exploration licence, the firm revealed today.

Following an initial reconnaissance by the firm on its 8,087 Libongo licence, which had been awarded to Botswana Diamonds earlier in the year, the firm applied for and obtained the broader licence. The balance of the reconnaissance licence remains valid, the firm said, and work is progressing with further portions able to be converted to exploration licences.

The new licence covers the ground where paleo-conglomerates have been identified. It is valid for four years and is renewable for multiple periods of four years. The licence ensures exclusive rights to prospect and also gives the holder priority for later conversion of the licence to a mining concession.

The firm’s planned bulk sampling programme, due to begin before the end of 2011 but after the rainy season, will determine whether the conglomerate occurrence on Botswana Diamonds’ ground is also diamondiferous.

In Botswana, the firm said its Prospecting Licence No. 04/2002 has been extended for a period of 12 months. This licence covers the AK8, AK9 and BK5 kimberlites.

Processing of samples from AK8 and BK5 are now complete. After a total of 883 tonnes of kimberlite was processed from AK8 some 11.03 carats were recovered, which translates to a grade of 1.25 carats per hundred tonnes (cpht). This is significantly below that reported from previous work by De Beers and African Diamonds.

The diamonds will be sent for valuation during this month, but the firm said it is most unlikely that the diamond values will be high enough to make the kimberlite commercial at the current grade.

At BK5 a total of 547 tonnes of kimberlite material was treated from historical stockpile material, while a total of 772 tonnes was treated form trenches excavated by Botswana Diamonds. The firm said that processing of this material yielded no diamonds.

AK9 is overlaid by a thick basalt breccias cap and the firm is reclogging the core to better understand the geology here at depth. It believes there are significant differences between micro diamond and macro diamond grade estimates and wants to understand these further.

“While we continue to apply for new ground in the Orapa area of Botswana the bulk sampling results on BK5 and AK8 were surprising and disappointing,” said John Teeling, Botswana Diamonds’ chairman. “We are re-examining the historical data and we are carrying out a thorough review of the AK9 kimberlite prior to a decision to bulk sample. Differences in results need an explanation.”

Keeling added that the firm believed more mines will be found in the Orapa region and that it had applied for certain prospecting licences there.

In Zimbabwe the firm is preparing to sample claims in the south east of the country, the target being a hard rock kimberlite similar to Rio Tinto’s Murowa mine.