Overview

Mine Type	Open Pit
Status	Care and Maintenance
Commodities	Diamond
Mining Method	Truck & Shovel / Loader
Production Start	...
Mine Life	...
Snapshot	On care and maintenance since February 2012.

Deposit type

• Kimberlite

Summary:

The surface area of BK11 is presently modelled as 9.6Ha and overburden, consisting of Kalahari sands and calcretes, is relatively shallow at, on average less than, 4m. The overburden is underlain by intensely calcretised and silcretised low grade kimberlitic material up to a depth of approximately 20m.

A comprehensive exploratory drilling programme was undertaken to fully delineate the position, extent and morphology of the BK11 kimberlite pipe below the surface to a depth of approximately 150m, as well as to establish the mineral resource potential.

The BK11 kimberlite has been shown to be a classic “champagne glass” shaped pipe with a large crater bowl filled with layered volcaniclastic deposits (K2-K3) and talus slope deposits, commonly known as country rock breccia, closer to the crater walls. A rather less-well delineated “neck” of more massive volcaniclastic kimberlite (K4) and basalt breccia underlies the crater. The kimberlite is covered with a thin veneer of up to, on average, 4m of Kalahari sands and then gradational calcrete/silcrete units which are believed to be dominantly weathered K1 material. Several shaley kimberlite units are present in the upper pipe, dipping gently outwards from the K1 “knoll” in the centre of the pipe.

The western and central side of the kimberlite pipe at BK11 is characterised by a cleaner and subsequently higher grade kimberlite, containing a higher proportion of clear white crystals with very little boart. However the eastern side of the kimberlite pipe at BK11 is characterised by dirty, heavily diluted and therefore lower grade kimberlite.

Mining Methods

- subscription is required.

Comminution

Crushers and Mills

Processing

- subscription is required.

Production