30 / 64
28
MODERN MINING
July 2015
feature
COUNTRY FOCUS –
BOTSWANA
C
ommissioned in 2012, Karowe –
which exploits the AK6 kimberlite
first discovered in the early 1970s
– has been a spectacular success
for Vancouver-based Lucara Dia-
mond Corp, which acquired the project from
De Beers and African Diamonds in two sepa-
rate deals signed in 2009 and 2010 respective-
ly. Designed to produce approximately 400 000
to 420 000 carats a year, the mine has met this
objective easily and in fact produced just over
430 000 carats in 2014. While the overall carat
production level has thus far been in line with
estimates, what was not foreseen at the plan-
ning and design stage of the mine was that the
orebody would have the ability to deliver large
diamonds on a regular basis.
“Over the past 29 months, Karowe has pro-
duced 70 stones of over 100 carats, including
12 of over 200 carats, and one of over 300,”
says Day. “The plus 300-carat stone, which was
recovered earlier this year, is a 341,9 carat Type
IIa diamond of exceptional quality. It could well
rank as the biggest gem-quality diamond ever
recovered in Botswana. There is some anec-
dotal evidence of a 372-carat stone having been
produced in the past but this – if the rumours
are true – was apparently of poor quality.”
Giving the background to the upgrade proj-
ect, Day says the plant as originally configured
and built was designed to treat the weathered
and transitional ore near surface. “It was well
understood from day one that as mining pro-
gressed the plant would have to be modified
Innovative
XRT
circuit now
in operation at
Karowe
The new XRT building at
Karowe diamond mine.
Construction of the US$55 million plant upgrade and
optimisation project at Lucara’s Karowe diamond mine in
Botswana’s Orapa Kimberlite Field (OKF) has been complet-
ed on time and on budget. Lucara’s Gaborone-based COO,
Paul Day, gave a presentation on the mine at the recent
Botswana Resource Sector Conference in Gaborone and
also discussed the upgrade project with
Modern Mining’s
Arthur Tassell on the sidelines of the conference. He says
that early results from the XRT technology installed as part
of the upgrade are extremely encouraging, with the circuit
thus far meeting all Lucara’s expectations.