Mine excursion
Cobalt and lithium are key in
manufacturing the batteries that power
these electric vehicles, and Namibia,
especially the central regions, have proven
deposits of lithium-bearing minerals.
The entire Erongo region is a geologist’s
dream, particularly if you are interested
in pegmatites. Pegmatites are formed
when granitic magma cools down and
produces exceptionally large crystals in
the final stages of crystallisation. These
crystals sometimes contain rare minerals
like lepidolite, which is used to produce
the necessary oxides in the production of
lithium.
While exploring the area with Johan
Coetzee, chief operating officer of Desert
Lion Energy, the deep purple colour of
the lepidolite is unmistakable. “This is
what Desert Lion Energy is interested
in,” explains Coetzee, as he finds his way
through the rubble and rock produced
after a recent blast. Desert Lion Energy’s
license area includes two main mining
sites, or pits, namely Helikon and
Rubikon. Two smaller pits are associated
with Rubikon, while more than seven
smaller workings are associated with
Helikon. In addition, about 32 historical
stockpiles are scattered throughout the
[14] MINING MIRROR NOVEMBER 2018
entire license area, on top of even more
artisanal workings, tunnels, and open pits.
Since 2017, when Desert Lion Energy
acquired the property, Coetzee and his
team have completed two blasts — one
at Rubikon and one at Helikon. These
blasts have uncovered what was once
underground stope-and-pillar mining
operations. “Both Rubikon and Helikon
were owned by Klochner & Company, who
in October 1990 sold to Namibia Lithium
Mines, a Namibian registered company
and a wholly owned subsidiary of South
African Afmin. However, the previous
owners mined petalite and tantalum that
were, and still are, used in the ceramics
and glass industries. Thereafter, a company
named Namibian Lithium Mines held the
mining rights, before Desert Lion Energy
bought the exploration rights in 2017,”
Coetzee explains.
The purple of lepidolites
Lithium, electric vehicles, and batteries to
drive this new technology, were, of course,
not in demand in the 1930s, with the
result that the previous owners dumped
the lepidolite (or lithium) on the dispersed
stockpiles found throughout the property.
“This material is enough to keep the
crushers and mills turning for at least a year
and a half,” says Coetzee.
Walking through the freshly blasted
old mining sites is not only a lesson in
the mining methods of yesteryear, but
a geology lesson par excellence. Purple,
pink, and marble white fragments
dominate the multicoloured piles of rock,
while the different layers of geological
history are on display right in front of you.
In these layers, the distinct pegmatites
and purple colour of lepidolites make
one wonder to what depths these
minerals have penetrated. When the
previous miners extracted and stockpiled
the minerals that host lithium, they only
touched the tip of the iceberg. Between the
old stopes (clearly visible after the blast),
wooden pillars, and even the remains of
rusted underground rail tracks and other
rubble, the lepidolite and pegmatite seams
run at a constant dip, deeper and deeper
into the unexposed interior of the earth.
Much of the mineralisation at Rubikon
and Helikon is still to be drilled and
remains open at depth.
“Desert Lion Energy has completed
significant work to understand the local
geology, which includes more than
20 000m of exploration drilling on the
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