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Project Status: On Hold
Exploration Stage: Bulk Sampling
Location: Between Vryburgand Warrenton
Project Areas: Brussels
Development Status: Bulk Sampling (Brussels), Pre Exploration on other 3
Licence Area: 239.91 km²

The Harts River Project comprises of a contiguous block of farms situated in the Northern Cape Province of South Africa between Vryburg and Warrenton, known as the Brussels Block.

History
The Harts River Project is based on a conceptual model of potentially diamondiferous gravels being present in the Dry Harts River and its tributaries. The drainages of this system are now small and ephemeral, but were of much greater significance in the past.

Sporadic small scale workings on large-boulder Rooikoppie-type gravels are found to the north of the area. These are presumed to have yielded diamonds, but no records of recoveries can be found. There is no record or evidence of any exploration having previously been done on any of the farms comprising the Harts River Project

Local Geology
The Brussels Area is situated at the upper end of the Harts/Dry Harts Valley, which is bordered on the east by high ground formed by outcrops of Ventersdorp lavas. The higher ground to the west is underlain by the Griqualand West Dolomite Sequence. The broad, open Dry Harts Valley narrows towards the north and abuts against the Griqualand West Dolomites at its northern end. Some remnants of Dwyka Tillite are scattered to the north and northeast, along the margins of the higher ground. The Brussels Area spans the entire upper portion of the terminating Dry Harts Valley and is underlain by calcrete and soil covered calcrete, indicating that this is a very old palaeo-river system.

Large areas of large-boulder Rooikoppie-type gravel are developed on top of thick calcrete to the north of the Project.

Within the project area, the Harts River valley is broad and open, with deposits of alluvium distributed over valley widths in excess of 5km. The floor of the modern valley consists predominantly of Dwyka tillite and shale. The valley has been interpreted as a Dwyka age erosion feature that was possibly scoured by glaciers into a pre-existing river valley. The widened fluvial valley became filled with glacial sediments after retreat of the ice. Different ages of alluvial gravels were deposited along a broad zone down the central axis of the valley. Three stages of gravels have been identified on the Blocks and surrounding areas. The oldest gravels, representing the earliest or first stage of alluvial deposition, are relatively fine-grained and poorly sorted and occur at elevations of 15m-20m above the present river level. The second stage of gravel formation was by fluvial deposition in channels. These gravels are medium to course grained and occur 7m-10m above present river level. The third stage of gravel formation is associated with the present day Harts River and this gravel occurs 2m-5m above present river level.

Location
The Brussels Area lies approximately 5km south of Vryburg and stretches for approximately 40 km from north to south. The Brussels Area comprises twelve farms or portions there of, contiguous from Lange Rand 821 HN to Blauboschkuil 835 HN.

The first exploration drilling and bulk test mining took place on the Remaining Extent (“RE”) of Portion 1 of Zamenkomst 819 HN located approximately 20km south of Vryburg on the Vryburg-Taung highway. The second completed bulk test mining took place at Gamabot HN also along the highway about 15 kilometres to the north.

A small scale alluvial diamond mining companies, were commissioned by PDF to carry out the bulk test mining work on the farms

Access and Infrastructure
Access to the Brussels Area is via the main R49 tarred road running between the towns of Vryburg and Warrenton and locally via farm tracks. The Dry Harts River runs through the area. The general infrastructure is good. A major water pipeline from the Harts Valley Irrigation Scheme passes through the western portion of the Brussels Block. Water from this source could possibly be used for larger scale mining in the future. The Eskom power grid is well developed in the general area and there is a railway and siding on the property.

Recent Exploration
Exploration drilling (more than 400 holes) identified and delineated gravel-bearing channels on all of the farms.along a 40km strike length suggesting a massive gravel resource. Two areas were selected for bulk sampling situated about 15 kilometres apart. The first exploration drilling and bulk test mining took place on the Remaining Extent (“RE”) of Portion 1 of Zamenkomst 819 HN located approximately 20km south of Vryburg on the Vryburg-Taung highway. The second completed bulk test mining took place at Gamabot 733 HN also along the highway. Small scale alluvial diamond mining companies, were commissioned by PDF to carry out the bulk test mining work on the farms.

The first 519,395 ton gravel bulk sample taken during 2006 was excavated and treated in order to ascertain the diamond grade and quality of the total gravel package. Subsequent 133,570 ton and 11 886 ton gravel bulk samples were excavated but different gravel layers were treated separately. The test work was successful and the company has achieved its target of identifying a large resource of more than 75 million cubic meters of diamondiferous gravel.

Management and Staff
As with the other projects, an on-site geologist is responsible for all exploration activities such as, mapping, borehole chips logging, bulk sampling monitoring and management and quality control.