Bulletin 2/2010 - Siempelkamp NIS

Metals – a mini lesson in material science
Gold – the name originates from the Indo-Germanic
language and translates into “shiny yellow”. In the
periodic table of the elements it has the symbol Au from
the Latin term aurum, “shining dawn”.
Copper – In the periodic table copper is identifi ed with
the symbol Cu. It is derived from the Latin term cuprum,
ore from the island of Cyprus, the stronghold of copper
mining in antiquity.
Platinum – In the periodic table it holds the symbol Pt.
It is derived from the Spanish word platina. The metal is
extremely corrosion-resistant and was used for the fi rst
time in Egypt in 3000 before Christ.
Nickel – In the periodic table this metal has the symbol
Ni. In its elemental form it could only be detected in 24
locations worldwide to date.
Iron – In the periodic table iron has the symbol Fe which
is derived from the Latin term ferrum. Verifi ably iron
was used for the fi rst time around 4000 before Christ for
making spearheads.
SIEMPELKAMP | FOUNDRY
Entrance to the gold-mine “The Super Pit” in Australia Mining excavator for rock mining
Metal mining: gigantic projects with a fi nal touch
Today metal-containing rocks are mined in large above-ground
mines. As a matter of principle, extensive bank-approved
feasibility and profi tability studies are completed in the forefront
of these operations. After the funding is approved, the planning
phase starts by determining which milling system best fi ts the
geological structure. Gigantic project sizes with outputs of more
than 250,000 t (275,578 US tons) of rock per day are very
common today. The yield of a gold mine is sometimes only 1.2 g
of pure gold per ton of rock. At a current gold price of
approximately 1,200 USD per ounce, even the mining of such
small amounts is considered economical. The most productive
mining areas for copper are Chile, Peru and Australia, for gold
and platinum the African continent and for nickel Russia and
Canada. Mining equipment is even supplied to places such as
Papua New Guinea and Burkina Faso.
At the actual mining sites, gigantic diggers with single shovel
volumes of up to 80 m³ are used. Dump trucks or heavy load
vehicles with cargo weights of up to 400 t transport the mined
material to crushing units.
For the last 20 to 25 years, crushers, autogenous mills and semiautogenous
mills as well as ball mills have been used to crush
different types of material. These mill types with rotating
cylinders that are mounted horizontally are used for the coarse
grinding and the subsequent fi ne grinding of the respective
mined rocks.