A second fieldwork programme at the six new prospecting licences (PLs) in Botswana awarded to the Sunland Minerals joint venture (JV) is planned for September, with initial work comprising sampling and geophysics.
The PLs were awarded this year to the private JV between diamond explorer and project developer Botswana Diamonds and diamond miner Alrosa for three years ending on March 30, 2020.
“I am delighted that we have been awarded this highly prospective ground in Botswana. This will enable us to work with Alrosa to deploy advanced exploration technology to areas which have not been looked at through this lens before,” says Botswana Diamonds chairperson John Teeling.
A team of geologists and mineralogists from Alrosa have arrived in Botswana to start the 2017 field exploration programme, which will focus on sampling and geophysical studies at the PL 260, in Orapa, and PLs 135, 235 and 234, in the Gope area of the country.
Spending eight weeks in the field, the team will conduct intensive systematic geochemical and geophysical work to gain a better understanding of the 2016 results, which were inconclusive of each licence, Teeling explains.
The Alrosa team is equipped with a mobile laboratory, enabling it to conduct mineralogical analysis of soil samples within 48 hours to improve the focus on its work and facilitate a faster exploration programme.
The transient electromagnetic method, a controlled-source induction resistivity method consisting of measuring earth responses to transmitter current turn-off and ensuing electromagnetic field decay, will also be used to provide a clearer indication of structures beneath the sand and basalt cover.
“On-site computing programs also allow for three-dimensional imaging to be shown to the exploration team in real time. You can see the shape, configuration and size of the kimberlites. This normally takes weeks, or even months, to obtain.”
Teeling says the six licence areas were selected following a detailed review of historical data by the Botswana Diamonds and Alrosa teams.
Four licences cover 3 135 km2, in the Central Kalahari Game Reserve (CKGR), and two cover 482 km2 in Orapa, also known as the ‘Kimberlite province’.
The CKGR area was selected as it is close to diamonds producer Gem Diamond’s Ghaghoo, formerly Gope, mine, and high-interest projects held by the Maibwe JV, comprising private company BCL (51%), mining company Future Minerals (20%) and information and communication technology company Siseko (29%).
Teeling explains that the Kalahari cover is thinner and that there are unexplained geophysical and kimberlite indicator anomalies, some of which are contiguous with existing pipes. The Orapa area – north-east of diamond mining company Debswana’s Letlhakane mine – was selected as it also hosts unexplained anomalies.
“There are 85 kimberlites in the Orapa kimberlite province, where eight are currently diamond mines or have previously been active diamond mines. The Orapa mine, owned by Debswana, a partnership between De Beers and the government of Botswana, is also the largest Tier 1 diamond mine by area in the world at 118 ha.”
Botswana Diamonds has a total of 20 diamond exploration licences, with ten in Orapa and ten in Gope.