Gary Coffman wrote:
On Thu, 01 Jul 2004 12:10:10 GMT, Seppo Renfors wrote:
Gary Coffman wrote:
On Tue, 29 Jun 2004 07:05:25 GMT, Seppo Renfors wrote:
This has a good story about the Great lakes Copper deposits.
http://www.geo.msu.edu/geo333/copper.html
As that article notes, 14 billion pounds of copper have been removed
from the area since the ancients were working copper there. Let the
enormity of that number sink in. There was an *awful lot* of copper
there in ancient times, much of it easily accessible from the surface.
My main interest was to show the formation of the copper deposits -
the volcanic activity that melted it (and other minerals with it).
Silver is/was found in fair quantities alongside the copper. What
isn't known - because nobody cares to find out, is the composition of
the metal used in the artefacts. It is ASSUMED to be pure copper.
The presence of silver inclusions *proves* the native copper was not
melted after being deposited.
....but only for that piece - not for any other piece. Further more
IIRC there is a method of laminating copper and silver sheet and
carving through one into the other. It is a Japanese technique IIRC.
It requires being heated under pressure, to the point the silver just
starts "sweating" and it brazes the sheets together. So silver in
copper can also be deliberate - as decoration.
Native copper is deposited by chemical
means, not volcanic melting and extrusion.
I already posted this earlier. It disagrees with you:
http://www.geo.msu.edu/geo333/copper.html
"chemical" doesn't get a single mention.
This naturally chemically
refined material is extremely pure copper. Here's a quote from the
Caladonia Native Copper Mine literature;
" The term "native" as used by mining men is synonymous with "pure",
"unadulterated" or "virgin". Keweenaw copper was found in a state of
such purity that a piece brought from underground could immediately
be beaten into pots and pans without smelting or refining."
This does not make a claim of "chemical" anything. Copper Sulfate
(Bluestone; blue, Roman or Salzburg vitriol) is soluble in water - but
dries to a blue crystal or powder. There are just nowhere near the
amount of acids or ammonia to it to be dissolved in!
Neubauer suggests that the ancients
would want to start with a piece of about the right size for the
object they wanted to make. At most that would be a lump weighing
a few pounds, in the vast majority of cases it would be a lump smaller
than a hen's egg. Even today, such lumps are relatively plentiful in
the copper belt. They were vastly more so 6,000 years ago before
modern industrial man started extracting copper from the region.
Knowing that mining was done by the ancient, including under ground
mining, then if the above was the case - where are all the piles of
copper not found to be suitable?
Some of the ancient mine tailings are still there, for example at the sites
on the Snake River near Pine City, Minnesota (Minnesota historical site
21PN11), or near Beroun, Minnesota (21PN86).
Interesting - I find only one ref to 21PN11, and it mentions nothing
about tailings. Nor do I see mentions of prehistoric tailings
anywhere. What is known of these tailings piles -do they contain a lot
of pure copper?
But most of the tailings
at Keweenaw were reworked by 19th and 20th century miners. The tailings
were rich and easily accessable, so it should be no surprise that miners
using more modern methods would have done this. 20th century miners
even reworked the tailings of 19th century mining operations as recovery
techniques, and power machinery, made it profitable to do so.
Again I can find no reference to prehistoric tailings having been
reworked. Modern ones have been:
http://www.atthecreation.com/wis.anc/%20cu.mines.html
http://www.scripophily.net/quinmincom18.html
At village sites there should exist copper scraps in considerable
quantities if such was simply discarded as "useless" if not big enough
for the task at hand. Nobody has pointed to such as yet at least.
Do you have evidence of the existence of such villages in the area?
I posted information of this in a reply to Tom.
From what I can gather, ancient native copper mining in the UP was
seasonal work, done from temporary encampments at the mine sites.
This is not a subject where I can claim any expertise, so I don't hold
that as absolute fact. Any hard evidence of permanent habitations
near the mines would be welcome.
I'm not certain of their "permanency", but villages they did have.
--
SIR - Philosopher unauthorised
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The one who is educated from the wrong books is not educated, he is
misled.
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