WINNING
Finstone as the economics of logistics have
made its exports less competitive). The
construction industry accounts for 80% of its
total product.
Tombstones, made from third-grade
granite, account for a significant 17% of
production (increasing to 25% in the case
of ‘Zimbabwe black’ granite quarries),
and this product has become increasingly
important to the local market. It used to be
a predominantly export market (80%), but
the doubling of logistics costs in dollar terms
means this has become a 100% local market.
Prices have stagnated over the past 20 years,
and the improved value-for-money to the
local market means volumes have doubled.
The percentage recovery varies
considerably according to the bench
locations throughout the pit, he says, with
some sections giving a 40% recovery but
some none (that is, not even third grade)
and is all waste. “That then simply goes into
backfill and waste. We throw top soil over it
and do rehabilitation afterwards, ” says Smit.
This occurs because the hillocks were formed
millions of years ago by immense pressure
from below and are under constant high
pressure. As soon as the weight is lifted from
the top by the mining process, the pressure
from below can crack the remaining granite,
which renders it non-mineable.
Mining methodology
There are three stages to the mining process,
says Smit: “For solid rock, diamond wire
Circular saws only suit wide benches, which is not the case at Springbok. They were in use only to level out the size of its benches in one location.
16_QUARRY SA| MARCH/APRIL 2019
www.quarryonline.co.za