An exercise underway to investigate the value of diamonds beneath the current Jwaneng mine pit, could add up to 20 years to the mine's lifespan, through the unlocking of hidden resources, Mmegi reported.

The Jwaneng Resource Extension Project (JREP) intends to probe the value of diamonds below the current limit of 400 metres and will be the largest resource evaluation programme ever undertaken, said the report.

The project encompasses and goes beyond the area being tapped into by the Cut 8 initiative, currently underway in Jwaneng, it said.

This week, Debswana officials said state of the art technology and equipment would be used for a drilling programme whose results will determine Jwaneng and the country's diamonds future.

Debswana's Regional Geologist, Martin Roberts said the drilling exercise was already underway and was scheduled to be complete by 2012, involving core samples of about 45 kilometres.

He said the drilling programme would evaluate the resource locked beneath the present Jwaneng pit, assessing the value between 400 metres and 850 metres.

"The extension of the indicated resource to below 400m is a key strategic priority at Jwaneng Mine and the scope of the JREP involves the delivery of an indicated resource estimate down to 850m below surface, which will then support mining operations for the next 20 years including all key expansion activities such as the Cut 8 Project and beyond," he said.

Roberts told Mmegi that while earlier studies at Jwaneng have shown that three diamond pipes below the mine extend to depths greater than one kilometre, little is known about the quantity or quality of diamonds between 400 metres and one kilometre, hence the current exercise.

The Regional Geologist explained that cutting edge technology and processes would be used to determine the value beneath Jwaneng Mine. This will include two 70 tonne drill rigs that have been procured and customised for the project, the largest ever used by Debswana.

He revealed that another innovation would be the use of micro-diamonds in resource estimation. Recent research has shown that the presence of micro-diamonds, less than 0.5 millimetres in diameter, can be used to extrapolate total diamond content, in cases where the proportion between the micro-diamonds and diamonds proper can be determined.

Roberts explained that the JREP would complement the ongoing Cut 8 project. The level at which Cut 8 is viable falls within the 400 metres of known resources, although the project will expose areas deeper than 400 metres.

"The accurate definition of the Jwaneng resource will help shape Jwaneng's and Botswana's future for the next 20 years and beyond," said Roberts.