Determining Geologic Sources of Native American Copper
"Parallax" skrev i meddelandet
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"Martin H. Eastburn" wrote in message
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Looking in my Bulletin 630 Bureau of Mines - Mineral facts and problems
Us. Dept. interior.
Page 263 - Notes that the U.S. was world leader in production of copper
from 1883 less 1934 when
economic conditions adversely affected domestic production and Chile
ranked first.
Artifacts of hammered copper have been found among Chaldean remains
dating back 4500 B.C. and
objects of copper have been taken from graves in the Fayum of Egypt.
Smelting began around 3800 B.C.
Smelting of raw material around 3500 BC [ Iraq ]
Romans mined copper in Britain.
Evidence of the first use of copper in North America was discovered by
archaeologists in pits on the
Upper Peninsula of Michigan and on Isle Royale in Lake Superior.
There are thousands of pits on Isle Royale alone.
The pits were excavated in mining and followed deposits of native copper
from surface outcrops.
Carbon dating of wood in the pits is 3,000 years old.
These stopped operation around 1000BC and started again around 100-200
AD elsewhere.
In 1709 copper from ore was produced in Simsbury , Conn
Hope that gives a little more info.
Martin - Wonderful book - I bought it many years ago and still like the
data.
I knew somebody who was doing trace elemental analysis of Cu
artifacts found in Apalachee mound areas of N. Florida using PIXE
analysis back in 1978. If I remember correctly, the source seemed to
be the Great Lakes region.
In an article which had good ref for almost everything I found a short
sentence which had no ref at all to it. That short sentence claimed that
Ancient(!) copper artifacts analysed from sites all over the world showed
that the copper origin from the Great Lake region. If that's right or wrong
I don't know since that one sentence wasn't possible to follow back to
analyse-tests at all. What I would like to know is if anyone among the
metallurgic specialist ever come accross copper artifacts where tests showed
or at least pointed to Great Lake copper origin?
Of course I plan to contact the scholar behind the article and before I have
heard reason for his statement in this special case I will not write his
name here. Might be that he in this sentence hasn't had as much as in all
other cases to back the conclusion/assumption (what ever) up as good as the
rest of the facts regarding Great Lake copper artifacts.
Inger E
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