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MODERN MINING
January 2015
Top projects
T
he under-estimation of the grade of
AK6 – and indeed its size – more
than 40 years ago resulted from
the limitations of the exploration
techniques and drilling equip-
ment then in use. Re-evaluation of the kim-
berlite starting in 2003 by De Beers revealed
that its grade was in fact a very respectable
16 cpht on average and that its size, just over
3 ha near surface, had been under-estimated as
it reaches a maximum area of 7 ha at 120 m
below surface.
De Beers and its partner in what was then
known as the Boteti Joint Venture, African
Diamonds, advanced the project through to a
Definitive Feasibility Study but did not actu-
ally take the kimberlite into production (with
African Diamonds keen to proceed and De
Karowe –
off to a
brilliant
start
Back in the early 1970s the newly discovered AK6 kimberlite near Orapa in Botswana was adjudged
to be sub-economic by De Beers, which put its grade at a paltry 3 cpht. Today this same kimberlite
underpins one of the most successful new diamond mines established in Africa in recent years – the
Karowe mine of Lucara Diamond Corp, which recently passed the million carat milestone. The mine’s
processing facilities are now undergoing a major modification to allow the treatment of harder ores
and enhanced recovery of large stones, as
Modern Mining’s
Arthur Tassell saw on a recent visit to the
site in the company of Paul Day, Lucara’s Gaborone-based COO.
DIAMONDS
Seen here (left to right) are Tony George, Paul Day and Dr John Armstrong. Day is COO of
Lucara and Armstrong is Lucara’s VP, Mineral Resources. At the time this photo was taken
George was Lucara’s Senior VP but he has since left Lucara to assume a similar role at Lundin
Gold, which – like Lucara – is part of the Lundin Group (photo: Arthur Tassell).