TORONTO (miningweekly.com) – Diamond explorer Pangolin Diamonds on Tuesday said that it had recovered diamonds from the Magi kimberlitic sandy tuff at its Tsabong North project, in south-west Botswana.

The Toronto-based explorer said that the drill hole samples from Magi005 had returned three micro-diamonds from two consecutive samples, located about 45 m to 49 m below the surface.

The micro-diamonds have a total carat weight of  0.000108 ct, with one diamond retained on the 0.150 mm sieve, Pangolin said.

The samples were described as reddish brown, fine- to medium-grained sandy tuff with more than 10% rock fragments of quartz and schist, and some micro faults/joints in-filled with siltstone. There were also similar sandy tuff horizons in the drill hole available for sampling.

The Magi core samples were submitted to the Saskatchewan Research Council Geoanalytical Laboratories, which are accredited to the ISO/IEC 17025 standard by the Standards Council of Canada as a testing laboratory for diamond analysis using caustic fusion.

While waiting for the results, Pangolin continued to work on the Magi area. A ground magnetic survey was successful in recognising two separate magnetic features close to the sandy tuff area.

Further, drill hole Magi008 was recently completed and ten split-core samples of fine- to medium-grained chaotic to banded sandy tuff were selected for diamond recovery work. These samples are on route to CF Mineral Research, in Canada. The results are not expected for at least one to two months.

Drill hole Magi007 was also recently completed and would be logged and sampled as necessary. Planning is now under way to step up the sampling and drilling programme at Magi.

At its Mmadinare project, in north-east Botswana, Pangolin said that confirmation testing of four grains - two of which were previously reported as micro-diamonds after mineral observation and two additional ‘possible’ micro-diamonds - did not pass diamond testing.

The significant numbers of mineral indicators recovered from the same set of samples, mainly ilmenites, were being prepared for micro-probe analysis to characterise their potential diamond affinity. The company said that it remained confident that the indicator-rich areas discovered to date and the presence of the SWS-21 intrusion containing mantle minerals with chemistry related to the diamond stability field, were indicative of the area's diamond potential.

CF Mineral Research, in Kelowna, Canada, using an energy-dispersive X-ray spectroscopy test, carried out diamond confirmation testing.

The first phase of follow-up soil sampling, designed to expand on the discovery of many indicator minerals in two separate areas within the project, is complete. The 148 samples would be processed by Pangolin in its dense media separation plant, located in Francistown, Botswana. Mineral concentrates would then be observed by an independent agent with confirmation testing, if necessary, by CF Mineral Research.

Meanwhile, Pangolin Diamonds, through its subsidiary Geocontracts Botswana, was issued, in terms of Section 16 of the Mines and Minerals Act, with a new prospecting licence for the exclusive right to prospect for precious stones within a 839 km² area of the Central district, Botswana.

Fieldwork would start shortly and would involve soil sampling for indicator minerals on a one-kilometre grid.