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Project Status: Operating
Exploration Stage: Pilot Mining
Orientation: Approximately 250km west of Johannesburg
Location: Situated within the Lichtenburg Diamond Fields
Project Areas: Patsema area
Licence Area: 168.74 km² (additional 188km² pending approval)

History
The Bakerville Project is located within the Lichtenburg Diamond Fields. The Lichtenburg section of the diamond fields was “officially” discovered in 1926, although it is thought that diamonds were being recovered from the area for at least two years prior to this.

Total recorded production from the Transvaal alluvial diamond fields, up to 1989, was 10.8Mcts, of which 7.5Mcts (70%) came from the Lichtenburg field. Of the Lichtenburg production, 6.9Mcts (92%) came from the Grasfontein-Welverdiend runs and potholes.

Production reached a peak in about 1931, and gradually tailed off since then. In the late 1970’s, approximately 30 small-scale diggers were recovering about 650cts per year.

In the early 1980’s, interest in the area was renewed with the release of a government survey report which indicated that undiscovered diamondiferous gravels may occur beneath sand cover within sinkholes and channels outside of the known major runs, which are located on eight farms. This period saw the arrival of foreign and local mining and exploration companies to the area.

Under the previous South African mineral laws, the mineral rights over many of the prospective properties in the area were held by the large mining houses, ruling out exploration by outside parties.

The new law however, has now “opened-up” these properties, providing new exploration opportunities for new entrants, such as PDF.

Local Geology
The alluvial deposits of the Lichtenburg area all rest on an irregular bedrock of Transvaal Dolomite, (Lyttleton and Monte Christo Formations) comprising dolomite inter-bedded with chert units. The gravels occur as patches and “runs”, representing an ancient drainage system. The runs are often punctuated by large sinkholes or potholes filled with gravel, which can be as much as 70m deep. Individual runs may be as much as 140m wide, and are often traceable for several kilometres, with diamondiferous gravel up to approximately 3m thick, with a reported average of 1.0-1.5m thick.

The gravel deposits owe their preservation to differential solution of the dolomite bedrock, which weathers less rapidly beneath the gravel “armour”. This, together with the more lush vegetation cover, protects the gravel from erosion. The gravels are made up of a chaotic mixture of water-worn pebbles, mainly of agate, quartzite and chert, with angular blocks, often large, of locally derived chert, in a sandy to clayey matrix, often rich in manganese and iron oxide pellets.

Stratification of the gravels is uncommon, but where fully developed, comprises, from the bottom up, a small-pebbled yellow gravel, overlain by coarse gravel, followed by the so-called “red gravel”, with a pale ferruginous gravel above this. In sinkhole fillings, the stratification exhibits steep dips, and even overturning in places, indicating that solution subsidence was active during and after deposition of the gravel.

The basal yellow gravel and the red gravel are generally the richest in diamonds, but stones may be found anywhere in the sequence.

The Patsema Area within the Lichtenburg Project is located approximately 20km north of Lichtenburg. It consists of four farms, or portions thereof, including Houthaaldoorns 2 IP, Zamenkomst 4 IP, Geluksdal 337 JP and Welverdiendt 361 JP.

Access and Infrastructure
The infrastructure in the district is good and the Patsema Area is readily accessible by well maintained tarmac and gravel roads. Electricity is supplied via the national grid. Although there is adequate water supply for domestic and agricultural purposes, water for mining operations requires pumping from the underground reservoirs using boreholes, which requires government approval.

Recent Exploration
An area covering approximately 8,5 km2 in the northern portion of the farm Zamenkomst was subjected to a ground gravity survey, this was followed-up by geological mapping, identifying and confirming potential gravel runs and potholes delineated from the gravity survey.

Various potential diamond-bearing gravel runs and potholes on the northern half of Zamenkomst have been drill tested. Potholes and runs identified by the drilling programme have been the focus of a bulk sampling programme in 2007 and early 2008. Large diameter (2.5m) Bauer boreholes (26) were drilled into the potholes. A bulk sampling plant consisting of a scrubber, 20tph DMS with X-ray recovery unit was established on Zamenkomst 4 IP which is currently treating the bulk samples. The earthmoving fleet consists of a 30 ton excavator and two 30 ton ADTs. Due to the absence of overburden and relatively short haul distances this matched the capacity of the plant to treat the volumes.

This exploration by PDF has identified an extensive diamondiferous gravel deposit on surface. Trenching and bulk sampling is now in progress to prove a resource large enough to sustain commercial scale diamond mining. The bulk sampling plant has been upgraded to a pilot mining scale with the addition of two 16’ pans and additional earthmoving equipment. The 16’ pans were added to the treatment circuit and feed concentrate to the DMS. This will double the capacity of the treatment plant. The capacity of the flowsort X-ray recovery has also been doubled to be matched with the increase in concentrate produced by the plant.

Future Exploration
Exploration and bulk sampling has mainly concentrated on the northern half of the farm Zamenkomst 4IP but this programme has now be extended to the adjacent farms and in particular onto the farm Houthaaldoorns 2 IP. Geological mapping and pitting on most of Houthaaldoorns has been completed as well as an in house feasibility study, which yielded positive results. The Mining Right application to allow full scale exploitation of the deposit was submitted in Q3 2009.

Management and Staff
An on-site geologist is responsible for the geological mapping, borehole logging and management of the drill and bulk samplingactivities. The earthmoving fleet and processing plant is managed and staffed by PDF.