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Location: East of Mobaye, southern Central African Republic (CAR)
Project Areas: Dimbi
Licence Type: Exploration
Development Status: Exploration
Operator: Pangea DiamondFields PLC
Licence Area: 995.00 km²
Licence Expiry Date: March 2009

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The Dimbi Project concession area is situated in southern CAR along the DRC border between the Oubangui River in the south and the Kotto River in the north. The town of Dimbi is situated within the concession area. Dirt roads link the towns of Dimbi and Kembe to the Oubangui River.

Access to the concession is by air from the capital, Bangui. An ex-military dirt airstrip is present at the town of Kembe. The concession is also accessible by road from Bangui, a distance of approximately 600km. The road is tarred for the first 200km and thereafter it is an all weather gravel road.

Entitlement to the concession is held by Dimbi Diamants SAU, a wholly owned subsidiary of Efidium.

In March 2007 a Mining Convention was signed with the government of the CAR in which the framework for future development of the project is defined. In terms of this agreement the CAR government becomes a 10% shareholder in the project and provides the necessary support for the development.

Operations within the concession area are currently based about 20km south of Dimbi town. A bulk sampling plant with associated earthmoving equipment was established on site during Q1 2007 and plans are currently in place to upscale this operation to the Pilot Mining phase during Q1 2008.

Water is plentiful in the area and is treated for potable usage. Power is supplied by diesel powered generators currently located at the Dimbi camp.

The oldest rocks occurring in the area are members of the mid- to lower Proterozoic Eburnian Supergroup. These poorly exposed schists and schistose quartzites are found as an approximately 4km wide belt within and paralleling the western boundary of the concession. The foliation of the schists generally dips relatively steeply towards the northwest.

To the east of the faulted contact with the Eburnian, the entire lease is underlain by a crudely synformal belt of meta-sediments of the upper Proterozoic Mokia Supergroup, known locally as the Fouroumbala Series. The sequence comprises, from the bottom upward; mica schists (not present in the lease area); quartzose schists; schistose sandstones and quartzites; overlain in places by carbonate rocks. The area is extensively blanketed with Kalahari sand.

The alluvial diamond deposits of the Dimbi area are associated with a palaeo-channel system of the Kotto River, which originally flowed southward past Dimbi. The main palaeo-channel was cut along the line of outcrop of the lower schist unit of the Fouroumbala, entering the Oubangui 2.5km northwest of Satéma, and was presumably controlled by the faulted contact. Diamonds are associated with three different depositional environments.

The Dimbi formation is a thick red-coloured sandy unit preserved on higher ground to the east of the main Kotto palaeo-channel. The Dimbi formation lies uncomformably on either a rough palaeo-weathered or fresh sandstone surface. The basal 0.5m of the formation is diamondiferous where it rests on the palaeo-weathered surface.

Tributaries draining the Dimbi formation flow into the Mbia River (Palaeo-Kotto River). Diamonds are found in hill-wash-type deposits within and in close proximity to the tributaries and are generally the richest deposits on the property. BRGM monitored pits in the Akongo River close to the bulk sample plant site reported grades of between 0.25 and 3.56 ct per cubic metre.

The third depositional environment is the Mbia River itself into which the tributaries drain adding diamonds to those already present in the river sediments derived from further inland.

A potential fourth style of mineralization has been identified with the discovery of a highly weathered lamprophyre intrusion.  Further exploration of this discovery has been delayed with a focus on developing resources in close proximity to the bulk sampling facility.
Exploration by hand-pitting and tractor-mounted auger drilling has resulted in the selection of a number of sites for bulk sampling.

Bulk Sampling
Bulk Sampling at Dimbi commenced at the end of Q1 2007 with a view to confirming resource grades and developing a sales parcel for valuation purposes. To date around 3,700 carats have been exported from the Dimbi Project and sales strategies are currently being investigated with a view to selling these stones early in 2008 to determine an average price per carat for resource determination.