involves the science, technology, and business of the discovery of gold,
in addition to its removal and sale in the marketplace. Gold may be
found in many places, most commonly rock but even sea water; in very
small quantities. More often it is found in greater quantities in veins
associated with igneous rocks, rocks created
by heat such as quartzite.
costs can be high in the exploration and removal of gold from the hard
rock mines, large companies are created in order to raise the money
necessary for the development of the mines, rather than the solitary
individual or small group associated with placer mining.
for gold is only worthwhile financially where there is a significant
concentration of it found in ore. The fixed
price of gold in 1934 increased from $20.67 U.S. to $35 U.S. per troy
ounce. This price remained fixed until 1968 which discouraged hard rock
mining for gold because increased inflation (which raised the cost of
mining production) prevented the mining companies from making a profit.
hard rock mining operations have even begun, companies explore areas
where gold may be found and scientifically analyse the rock. The actual
gold originates deep within the earth in places called pockets.
These pockets are filled with gold, heavy ore, and quartz. If enough
gold is discovered in the ore, the technological process of hard rock
miners dig a tunnel into the solid rock. During the 1930s, miners working
for the companies dug these tunnels by hand, a very labour-intensive
undertaking. Miners often risked their health, digging with picks and
shovels during long shifts in these dark, damp tunnels, building the
shafts and carting out the ore.
underground involved falling rock, slips, and explosions, but the workers
also had to inhale dust into their lungs in this era before safety regulations,
safety equipment, and improved ventilation. The miners were willing
to take the risks in order to provide for their families.
milling process may be broken down into three basic procedures:
the ore by size
miners raise the ore out of the mine in wheeled carts pushed on rails
and take it down to the mill. The rock fragments are sorted according
to size in a grizzly, a device consisting
of a series of spaced bars, rails, or pipes, above a forward moving
conveyer belt to a crusher machine.
washing, a shaker screen filters out
fragments of less than 1/2 inch diameter into a fine ore bin, or box.
Larger ore fragments are pulverized or crushed in the crusher. The fine
ore is fed by conveyer belt to a ball mill,
a rotating steel cylinder filled with tumbling steel balls which further
crushes the fragments to a consistency of fine sand or talcum powder.
This powder is fed into a thickener with a cyanide
and water solution to create a sludge (a sticky, mud-like material).
The liquid sludge is diverted into holding tanks and referred to as
the pregnant solution - a liquid sludge containing 70 percent of the
drawn from holding tanks through a clarifier, a device that removes
all the remaining rock or clay from a pregnant solution. In the next
step, the material is taken to a de-areator tank
that removes bubbles of air and further clarifies the solution.
added in dust form to the de-areated solution, which is drawn under
pressure through a filter press which causes
the gold and zinc to precipitate onto canvas (heavy cloth) filter leaves.
This zinc-gold precipitate (condensed into a solid) is then cleaned
from the filters while extreme heat burns off the zinc.
through the filters is chemically tested for gold residue before being
discharged into tailings ponds. Gold bearing water may be passed through
the filtering process several times to remove all of the gold and separate
it from impure substances.
from the ore through the milling process is poured into bricks that
are shipped to be assayed and sent to the Royal Canadian Mint in Ottawa,
where coins are struck (made).
of the milling process are three types of tailings rocks which cover
the landscape of Wells. Hydraulic mine tailings are the resulting rocks
washed down the mountainside with water monitors. Another type of tailings
is taken out from the mountainside during tunneling.
left over after being processed through a mill are referred to as mill
tailings. Tailings have altered the shoreline around Jack of Clubs Lake
and have the appearance of pale yellow, layered mineral sands.
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