Connection to the Earth Science Curriculum Essential Lessons: 1) What was the purpose
of the stamper? 2) How was copper sorted
from the rest of the
poor rock? Big Idea 9: Humans significantly alter
the Earth.
E.ES.E.5
Human Impact- Humans depend on their natural and constructed
environment.
Humans change environments in ways that are helpful or harmful for
themselves
and other organisms. Vocabulary
Osceola Township
Board PO Box 437 Dollar Bay, MI 49922 The Stamp Mill Ruins are considered unsafe for visitors by the Osceola Township Board. Please only observe from the road or nearby public playground and do not approach the ruins. |
Ginormous
Stamp Mill Ruins At this site you
will see a mill stamper. These
were used
during the mining years to crush rock that was pulled up from the mines. The rock was then
separated into poor rock, left
over or waste rock, and ore, the rock that contained copper.
Figure
1:
Stamper
This is a stamper that was unable to be dismantled and is one of the few of its kind remaining in the world Copper mining
began in the 1840’s. Rock
was pulled up
from the mines and sent to this stamper
by railcar for rough stamping. The
stamper would crush the rock into smaller pieces, which would be sorted
into
ore, rock with copper, and poor rock, or waste rock.
The ore rock would
then go through another round of pulverization to break down the pieces
even
further. Once the
ore pieces were
crushed to pebble size they were considered stamped sands. These sands were crushed
rock mixed with
copper. The sands
would be sorted into
jigs to obtain as much copper as possible.
A jig is a smaller basin filled with water with a
screen. The jigs job
was to further separate the pieces based on the law of separation. This law states that
heavier or denser pieces
will settle toward the bottom while the less dense or lighter pieces
would stay
at the top. Copper
has a higher density
than the stamp sands. So
gravity
assisted the pieces with a heavier concentration of copper and pulled
them to
the bottom, while rock with little to no copper would float toward the
top. Figure
2:
Stamper Pedestals
Picture By: Carolyn Bolduc The last stop for
the rock was the wilfley table. The
table was tilted at an angle with a tray on top.
The rock/water mix was poured over the table. The lighter stamp sands
would wash over the
table while the denser rock with copper would catch in the seams of the
tray. The ore could
then be
collected. The
stamp sands mixed with
water and created slurry. This
slurry
was piped out and deposited directly into Torch Lake.
The sands are still there along with concerns
about the effect the sands have on the environment.
Figure
3:
Stamp Mill Process
Historic American Engineering Record. Heritage Conservation & Recreation Service. Delineated By: Eric M. Hansen, 1978. Logging Question: How many pillars
are still standing at the site? a) 3 b) 4 c) 8 |
References Forgrave, Mike.
(2001). The Copper Country Explorer. Retrieved
July 29, 2011 from:
http://www.coppercountryexplorer.com/
http://www.youtube.com/watch?v=ORYO9VZ9T2M&feature=related
http://www.youtube.com/watch?v=ZFKNCD-w2uk
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