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  #101   Report Post  
Old July 1st 04, 11:58 PM
Gary Coffman
 
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Default Copper Casting In America (Trevelyan)

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. Native copper is deposited by chemical
means, not volcanic melting and extrusion. 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."

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). 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.

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?
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.

Gary

  #102   Report Post  
Old July 2nd 04, 05:28 AM
Eric Stevens
 
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Default Copper Casting In America (Trevelyan)

On Thu, 01 Jul 2004 01:33:16 -0500, Tom McDonald
wrote:

Eric Stevens wrote:

snip


What about radiographs cited by Mallery? These have been mentioned
several times.


Eric,

Gary has discussed this several times. In essence, the
radiographs on Connor's web site cited by Mallery were
apparently not cast. What Mallery considered bubbles
characteristic of cast copper appear to be, with one exception,
*not* the type of bubbles one finds in casts of copper of the
purity seen in the artifacts.


Apart from the fact that the radiographs on Connors site are by no
means the only evidence, the presence of one exception should not be
ignored.

The sole exception, the artifact labeled R666 (Riverside site
artifact number), or 55786 (Milwaukee Public Museum catalog
number--where the artifact is curated), does show the typical
porosity. However, I don't think anyone thinks that the
artifact is an example of intentional casting, but rather of
accidental or natural (e.g.: forest fire) melting of a bit of
copper.


I don't for one minute expect that an ordinary forest fire would melt
a copper artifact of that size.

OTOH, some of the radiographs clearly show annealing twins, and
linear voids characteristic of smithing.

This has been discussed before in this thread, perhaps before
you returned. If any of this seems new to you, you might want
to read the thread in Google groups.


How about the several times I posted the reference to the reports of
New York Testing Laboratories and the National Bureax of Standards. I
quoted Mallery in Message-ID:
. Yuri Kuchinski later
picked it up and requoted it in message
om... and I cited my
original article again in Message-ID:
.

Important words from the quote from Mallery include:

"X-RAY EXAMINATION:—The tools were radiographed using
standard techniques. A review of the radiographs led to the
following observations:— # I—The three tools were originally cast."

"The specimens are originally cast but apparently have been
reheated and worked to some extent."

"Following this report, six leading American museums furnished
tools from the United States, Canada, Mexico, Guatemala, and
Peru for testing. Various metallurgists who have examined the
micrographs of these tools concur in the findings of the New
York Testing Laboratories, Inc. that many of the specimens
examined have been cast. Dr. George P. Ellinger, metallurgist
for the National Bureau of Standards, said, after examining the
submitted specimens, "The presence of cuprous oxide in the
interior of the tools tested and the concavity caused by
shrinking justify the conclusion that the vast majority of the
ancient tools were cast."


These words are unambiguous and do not depend solely on the
interpretation of the information posted on Connor's site.




Eric Stevens

  #103   Report Post  
Old July 2nd 04, 06:04 AM
Philip Deitiker
 
Posts: n/a
Default Copper Casting In America (Trevelyan)

Eric Stevens says in
:

These words are unambiguous and do not depend solely on the
interpretation of the information posted on Connor's site.


This is not so hard to see, copper comals made in Guerrero and
Xoahaca are made in much the same way they were previous, the
comal being the primary 'tool' made in the region. These comals
are not cast, they are pounded. I am by no means a leading
expert on the totality of tools, but the comal appears to be
something that was large and consumed alot of the copper
generated for non-ornamental purposes.
Maybe it is difficult for a person in New Zealand to have
access to this information; however I have seen at least 2 video
reports on the manufacturing of the comal, and they are not
cast. The most similar cultural item I have seen is the hammered
woks created from iron in china (which you can buy on the home
shopping network if you are lucky). Woks being more
sophisticated with handles, whereas the comal is just a large
concave piece of copper.

I would not be surprised if the Andeans and Mesoamericans cast
copper, they certainly has made many advances in metallurgy,
however I think, with regard to tool use, one has to question
the utility of casting when hammering out the metal requires
less heat and is amicable to all kinds of transformations
without need of a mold.

BTW, this whole conversation is repetitious and boring. We
start this whole thing by some idiot argueing that copper
smelting technology came from europe, when in fact the
technology in the new world clearly initiated independently in
south america and spread in the opposite direction. Of course if
the eurasians can invent copper smelting and then casting, gee
it seems like someone who knows enough to smelt copper could, if
he so desired, to cast it also, a minor variation in a well
advanced technology. Thus the cultural connection of either to
eurasian influence is dubious even if it did exist. By the fact
you have some expert pointing to a number of cultures in which
we KNOW that copper smelting developed independently of eurasia,
as evidence for copper casting is not the way to 'cast' an
argument for the diffusion of casting technology from europe.
More or less its a way to disprove that any artifacts that were
cast in the new world were the result of european influences.

Are you arguing for the sake of arguing or is there a point and
direction to your argument?

BTW, Now that we have decided to dabble south. Consider the
obsidian knives and decorative glasswares of the mesoamericans.
What kind of parallels do these have in the old world. This was
a fairly advanced technology.



--
Philip
- - - - - - - - - - - - - - - - - - - - - - - - - - -
Mol. Anth. Group http://groups.yahoo.com/group/DNAanthro/
Mol. Evol. Hominids http://home.att.net/~DNAPaleoAnth/
Evol. of Xchrom.
http://home.att.net/~DNAPaleoAnth/xlinked.htm
Pal. Anth. Group http://groups.yahoo.com/group/Paleoanthro/
Sci. Arch. Aux
http://groups.yahoo.com/group/sciarchauxilliary/
  #104   Report Post  
Old July 2nd 04, 07:02 AM
Seppo Renfors
 
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Default Copper Casting In America (Trevelyan)



Gary Coffman wrote:

On Thu, 01 Jul 2004 08:26:52 GMT, Seppo Renfors wrote:
Gary Coffman wrote:
On Tue, 29 Jun 2004 05:48:01 GMT, Seppo Renfors wrote:
Gary Coffman wrote:

[..]
Again, porosity is the problem, and that should show up on
radiographs, as it does for R666 (which certainly shows evidence
of being melted in atmosphere, though not necessarily evidence
of being cast), but none of the other artifacts presented show
that sort of porosity.

See:
http://www.iwaynet.net/~wdc/copper.htm

The 4th and 5th pictures down.

Those pictures do not show any evidence of the characteristic
porosity copper casting would produce.


They disagree with you as it states "The casting bubble can clearly
been seen...."


And as I note below, they are quite wrong. It is rather obvious that
they have little practical experience or knowledge about working
native copper. It behaves significantly differently from other metals
when melted or cast.


Copper is copper no matter what part of the world it is in. ALLOYS
vary from place to place. So I find it hard to accept Michigan "native
copper" is much different from that here in Australia.

I would also direct your attention to this:
http://people.uncw.edu/simmonss/P6030052.JPG

There is little question this has been melted - and where are the
obvious faults?

Your authorities are a dentist, an engineer whose expertise is with
iron and steel, and one chemist (who disagrees with 4 others at his
school). Frankly, not a very impressive collection of authorities on
the metallurgy of native copper.


If you go to purchase a bottle of wine, which is the most important -
the label on the bottle or the taste of the content? The above is
pointing to the label, ignoring the content.

The single large surface
bubble is a blister, common when the surface of a wrought piece
is overheated. Compare it to the radiograph of R666. The latter
does show the characteristic deep pattern of porosity of an at least
partially melted copper object.


[..]

--
SIR - Philosopher unauthorised
-----------------------------------------------------------------
The one who is educated from the wrong books is not educated, he is
misled.
-----------------------------------------------------------------
  #105   Report Post  
Old July 2nd 04, 07:42 AM
Seppo Renfors
 
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Default Copper Casting In America (Trevelyan)



Tom McDonald wrote:

Seppo Renfors wrote:

Tom McDonald wrote:

Seppo Renfors wrote:


snip

http://www.dayooper.com/Networks.JPG

The copper may well be 99% pure - what about the rest? It isn't every
day people find huge lumps of pure copper without impurities embedded
within it. This is the dilemma that people bypass and ignore.

This has a good story about the Great lakes Copper deposits.
http://www.geo.msu.edu/geo333/copper.html

[..]



Seppo,

Thank you for the urls.

From the second link:




Hang on a sec. What about the first? After all it is THE more
important one.


Seppo,

I don't think so. That's why I focused on the other url.


THAT or similar and worse are the condition of the copper you will
find frequently.

http://www.dayooper.com/Networks.JPG

You tell me how the hell you can make an axe head out of that! You are
in total denial about this problem.


I don't know the matrix enclosing the copper in this sample.


It is enough to know it exists.

However, as you note below, stone hammers would work fine to
crush rock containing the copper. Then the copper bits could be
picked out of the debitage.


....and how do you think it is made into one large lump -eg to make an
axe head? Spit on it an hope it glues it together?

What is the problem? No one has maintained that all the copper
used was in the form of pure copper nuggets.


Oh but that IS the implication.

"Michigan’s copper deposits were remarkable for their quality
and purity. Bands of native copper were contained in outcrops 2
to 8 miles wide and of varying depth. The surface deposits first
attracted the notice of Native Americans who dug out the easily
accessible chunks and fashioned copper tools and adornments from
them."



Do you REALLY believe they were cliffs of PURE copper?


No, of course not. Don't be silly.


Note the words
"were contained in". Then see the Networks.JPG and you will get an
idea of the meaning of the words.


What is your point? We know that the folks back then
eventually had to mine the copper. We know the tools they used
to do so. Had most of the copper been in large lumps, the tools
used for mining would not have been large stone hammers, wedges,
fire, etc.

As Gary has pointed out, it's a bitch to cut pure copper, even
with steel tools. Smart folks, like the Indians of those days
were (still are, BTW), would most likely have preferred to
extract the copper in more manageable sizes.


So mining involves exactly the type finds (and worse) I pointed to
with the URL.

I am aware of one piece of copper 17 ton of it (Yank ton presumably -
a short measure). It was found on the bottom of Lake Superior. I'm
also aware of another large find of several tons, but a VERY long way
underground in a modern mine. Neither kind of find was available to
the native people.


And nor would they have preferred them if they were available.
There is a huge chunk of copper still in a mine, which the
ancient Indians tried to extract, but appear to have given up as
a bad job. Still, they seemed to do OK without it.

BTW, what is your fascination with size here? It's not really
relevant.


Isn't it? Why else do claims of "more manageable sizes" get made? Also
mentions of "egg sized" etc... etc... indicating a contiguous piece of
pure copper of the required size. This right size lump message has run
right through the thread by the naysayers.

So mining appears to have *begun* where copper deposits were on
the surface. This makes sense, as there was also drift copper
(over a wider area than just the UP mining areas), and folks
early on seem to have selectively used lumps of copper that
needed no processing. While this might not have been an every
day event, it clearly was common enough to produce many of the
copper artifacts in the region.

As to mining the copper:

"They [Indians] dug pits in the ground and separated the copper
from the stone by hammering, by the use of wedges, and,
possibly, by the use of heat. Thousands of hammers have been
found in and about the old pits."



The claimed method is not fact - only assumption. The "fact" is the
finding a lot of "hammers". They are only proof of pounding or
hammering - which can mean crushing of rock containing the copper.


Yes, that too. Or do you imagine that the hammers were
single-purpose tools?


Indeed they are. A hammer is properly described as a "hand percussion
instrument" - a single purpose tool.

It seems that these folks picked the visible copper out of the
debitage after beating the bejesus out of the rock. That seems
reasonable to me, as there seems to have been quite enough such
copper available to make other methods of extraction unnecessary.

The dilemma you refer to does not seem to exist.


THAT is nonsense. I have provided you with a good example of the
nature of it. It isn't the first time I have done it either - and
haven't even had to use the same pictures.


Re-read (read?) what I wrote directly above the bit you went
off on.


"The dilemma you refer to does not seem to exist." - does exist - I
have provided evidence of it in the URL above.

Indian people
developed the technology they needed to extract the resource
they wanted.


Obviously, only you don't know what method they used. Nobody has
bothered to find out.


Ever heard of 'archaeology'? Or haven't *you* bothered to find
that out?


You are rejecting some methods, and still only recognise your own
unsubstantiated version that suits your view. You do not accept
crushing and melting to separate the copper from rubbish - to make it
into "more manageable sizes"!

http://www.iwaynet.net/~wdc/crucible.htm

"Neiburger says these bubbles are caused by hot gas in molten metal
and as such are solid evidence of copper melting and casting."

....not to mention other claims made on that site.

They may have developed copper casting technology
as well. Since smelting wasn't necessary, casting would have
been a stand-alone technology. It wasn't beyond the capacity of
the Indians of the upper Great Lakes; but it also wasn't necessary.



Then you can perhaps point to the huge piles of discarded copper that
was useless because it looked like that stuff in the first URL. There
have been vast amounts mined by the native people - where are the
rejected copper piles?


Some is still there.


Where?

I assume, but do not know, that modern
prospectors and miners would have processed such piles, as they
would probably have been a good source of copper for smelting.
Or do you think that respect for the past would have prevented
the modern copper industry from utilizing that resource?


I did anticipate this answer already :-)

Where is the evidence they did so? Remember "not knowing" means
"doesn't exist", in your methodology of argument. The ancient mining
sites are numerous - therefor scrap copper sites would be at least as
numerous - but more likely far more numerous as village sites don't
have them either. Therefor the recording of the use of these piles of
"copper rubbish" by early colonials is that much more likely to exist
in multiple places - IF it happened at all. Now all you have to do is
support your "what if" with facts or see it disappear - without even
so much as a puff of smoke.

"No large pieces of scrap copper were found, and this could be an
indication that the Cahokia copper craftsmen "had learned to smelt
copper scrap"." - ibid

"Perino noted that while it is known that many copper objects were
made at Cahokia, "nowhere in the area has anyone found any copper
scrap"." - ibid

A broader look for copper s/melting.

http://www.shef.ac.uk/assem/2/2dung2.html

(Review of book)
Early Metal Mining and Production - Edinburgh University Press 1995
ISBN 0 7486 0498 7
"The use of native copper in North America is explored in some detail
but the smelting and alloying technology of South America is barely
mentioned."

http://people.uncw.edu/simmonss/lamanai.htm

"Copper and bronze (copper-tin and copper-arsenic) began to arrive at
Lamanai during the 13th century AD. Provenience studies conducted by
Dr. Dorothy Hosler at the Massachusetts Institute of Technology
revealed that the copper used to produce many of these items was
obtained from West Mexican ore fields."

Note specially this:

http://people.uncw.edu/simmonss/P6030052.JPG

Where is the "obvious" evidence of it being cast?

There is a section on metals (pp.183-350) in the volume edited by
David A. Scott and Pieter Meyers, "Archaeometry of Pre-Columbian Sites
and Artifacts". What is says I have no idea

See this for an idea - not yet implemented?
http://www.socarchsci.org/ARK96.htm
LASER ION MASS SPECTROSCOPY AS A TOOL FOR ARCHAEOMETRY


If the copper is pure is not known because nobody has bothered to find
out.


And yet, they did. If you aren't going to read this thread any
better than you appear to have done in this sentence, why post?


Are you now claiming an extensive analysis of artefact has indeed been
done? I'm sure you would be eager to point to them -if they exist. So
where are they? As far as I know, only those few artefacts under
discussion have been analysed to any degree.

Silver does exist with/alongside/embedded in with copper in that
area - as are other minerals, including arsenic.


Sure. Copper artifacts have been found with just those
inclusions. However, silver isn't found in them as an alloy
(which might happen if the material were cast), but as
inclusions (which would happen if the copper-silver cobble were
worked by smithing).


How do you know that when the analysis hasn't been done?


--
SIR - Philosopher unauthorised
-----------------------------------------------------------------
The one who is educated from the wrong books is not educated, he is
misled.
-----------------------------------------------------------------


  #106   Report Post  
Old July 2nd 04, 08:50 AM
Tom McDonald
 
Posts: n/a
Default Copper Casting In America (Trevelyan)

Eric Stevens wrote:

On Thu, 01 Jul 2004 01:33:16 -0500, Tom McDonald
wrote:


Eric Stevens wrote:

snip

What about radiographs cited by Mallery? These have been mentioned
several times.


Eric,

Gary has discussed this several times. In essence, the
radiographs on Connor's web site cited by Mallery were
apparently not cast. What Mallery considered bubbles
characteristic of cast copper appear to be, with one exception,
*not* the type of bubbles one finds in casts of copper of the
purity seen in the artifacts.



Apart from the fact that the radiographs on Connors site are by no
means the only evidence, the presence of one exception should not be
ignored.


Eric,

It isn't being ignored. It has been, and continues to be,
discussed. It would be a stronger candidate for evidence of
intentional casting if it were not a shapeless blob that somehow
got melted.


The sole exception, the artifact labeled R666 (Riverside site
artifact number), or 55786 (Milwaukee Public Museum catalog
number--where the artifact is curated), does show the typical
porosity. However, I don't think anyone thinks that the
artifact is an example of intentional casting, but rather of
accidental or natural (e.g.: forest fire) melting of a bit of
copper.



I don't for one minute expect that an ordinary forest fire would melt
a copper artifact of that size.


First, what do you mean by "of that size"? The dimensions
noted are about the size of a little girl's palm (about 2.4" x
1.6" x .3"), with a weight of about one pound. (The weight
given in grams seems to have misplaced the decimal; I doubt that
such a hunk of copper would weigh 12 pounds.)

Second, what do you mean by 'ordinary forest fire'? Forest
fires can range from about 700 C to about 1200 C. The high end
of that scale is well over the melting point of copper, at 1084
C. It does not appear that your incredulity can rule out forest
fire here. I found this on a site about satellite detection of
forest fires:

"For temperatures associated with fires (eg 1,000k-1,500K) the
peak wavelength will be considerably shorter (a few µm)."

http://ceos.cnes.fr:8100/cdrom-00b2/...t/firedet1.htm

or

http://makeashorterlink.com/?N156324B8




OTOH, some of the radiographs clearly show annealing twins, and
linear voids characteristic of smithing.

This has been discussed before in this thread, perhaps before
you returned. If any of this seems new to you, you might want
to read the thread in Google groups.



How about the several times I posted the reference to the reports of
New York Testing Laboratories and the National Bureax of Standards. I
quoted Mallery in Message-ID:
. Yuri Kuchinski later
picked it up and requoted it in message
om... and I cited my
original article again in Message-ID:
.


You've told me that you haven't been able to find the report
from the NYTL, and (correct me if I'm wrong), from the National
Institute of Standards and Technology (the successor to the
National Bureau of Standards). Thus, we don't know what the the
full reports state, and don't know whether the results might be
interpreted differently today.

I've just emailed both the NYTL and the NIST about these
reports. Probably a lost cause, but what the hell.

However, please note that the NBS report Mallery cites on page
223, Letter-Circular 444, July 13, 1935, is _not_ the source of
the quotation by Dr. George P. Ellinger on page 225, quoted by
you below. The quotation by Ellinger has to have been made
_after_ the NYTL report; and as I note below, the NYTL testing
had to have been done at least a decade after NBS L-C 444.

We don't know whether Ellinger is being quoted from a report, a
letter, a conversation, or what. We can't follow up on this to
see whether Mallery got it right.



Important words from the quote from Mallery include:

"X-RAY EXAMINATION:—The tools were radiographed using
standard techniques. A review of the radiographs led to the
following observations:— # I—The three tools were originally cast."

"The specimens are originally cast but apparently have been
reheated and worked to some extent."


This was the testing done at the behest of James A. Ford of the
American Museum of Natural History, per Mallery. Ford began his
tenure at the Museum sometime in 1946:

http://www.mnsu.edu/emuseum/informat...ord_james.html

or

http://makeashorterlink.com/?J567224B8


"Following this report, six leading American museums furnished
tools from the United States, Canada, Mexico, Guatemala, and
Peru for testing. Various metallurgists who have examined the
micrographs of these tools concur in the findings of the New
York Testing Laboratories, Inc. that many of the specimens
examined have been cast. Dr. George P. Ellinger, metallurgist
for the National Bureau of Standards, said, after examining the
submitted specimens, "The presence of cuprous oxide in the
interior of the tools tested and the concavity caused by
shrinking justify the conclusion that the vast majority of the
ancient tools were cast."


Even if Mallery quoted accurately from the NYTL and George
Ellinger, we are still left with the problem that neither the
NYTL report, or the statement by Ellinger, state what Gary and
Paul assure us would have been obvious from the radiographs;
characteristic porosities. Internal small bubbles. Many.

Instead, the NYTL report talks about 'course-grained copper and
.... several annealing twins' for the axe and chisel; and 'pure
copper crystals or grains' for the spearhead. These were from
100x magnifications of sections taken from the artifacts. No
bubbles mentioned. As for the radiographs, the NYTL only says
'[t]he specimens were originally cast....' No mention of
bubbles; no details as to how they arrived at that verdict.

The later testing of other artifacts Mallery mentions is
entirely unsupported by even the details given for the NYTL
report, with the exception of Ellinger's mention of cuprous
oxide in the interior of the tools tested, and the gross
observation of concavities in the tools (all of them? some of
them? which?). Again, we don't seem to have any way of
tracking down the source of the Ellinger quotation.

None of these tools appear to have been radiographed. Mention
is made only of micrographs. And no mention whatsoever of
small-bubble porosities.



These words are unambiguous and do not depend solely on the
interpretation of the information posted on Connor's site.


For sufficiently small values of 'unambiguous', perhaps.

Tom McDonald
  #107   Report Post  
Old July 2nd 04, 08:53 AM
Seppo Renfors
 
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Default Copper Casting In America (Trevelyan)



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
-----------------------------------------------------------------
The one who is educated from the wrong books is not educated, he is
misled.
-----------------------------------------------------------------
  #108   Report Post  
Old July 2nd 04, 09:03 AM
Tom McDonald
 
Posts: n/a
Default Copper Casting In America (Trevelyan)

Seppo Renfors wrote:


Tom McDonald wrote:

Seppo Renfors wrote:

Tom McDonald wrote:


Seppo Renfors wrote:


snip

http://www.dayooper.com/Networks.JPG

The copper may well be 99% pure - what about the rest? It isn't every
day people find huge lumps of pure copper without impurities embedded
within it. This is the dilemma that people bypass and ignore.

This has a good story about the Great lakes Copper deposits.
http://www.geo.msu.edu/geo333/copper.html

[..]



Seppo,

Thank you for the urls.

From the second link:



Hang on a sec. What about the first? After all it is THE more
important one.


Seppo,

I don't think so. That's why I focused on the other url.



THAT or similar and worse are the condition of the copper you will
find frequently.


http://www.dayooper.com/Networks.JPG

You tell me how the hell you can make an axe head out of that! You are
in total denial about this problem.


I don't know the matrix enclosing the copper in this sample.



It is enough to know it exists.


However, as you note below, stone hammers would work fine to
crush rock containing the copper. Then the copper bits could be
picked out of the debitage.



...and how do you think it is made into one large lump -eg to make an
axe head? Spit on it an hope it glues it together?


What is the problem? No one has maintained that all the copper
used was in the form of pure copper nuggets.



Oh but that IS the implication.


"Michigan’s copper deposits were remarkable for their quality
and purity. Bands of native copper were contained in outcrops 2
to 8 miles wide and of varying depth. The surface deposits first
attracted the notice of Native Americans who dug out the easily
accessible chunks and fashioned copper tools and adornments from
them."


Do you REALLY believe they were cliffs of PURE copper?


No, of course not. Don't be silly.




Note the words

"were contained in". Then see the Networks.JPG and you will get an
idea of the meaning of the words.


What is your point? We know that the folks back then
eventually had to mine the copper. We know the tools they used
to do so. Had most of the copper been in large lumps, the tools
used for mining would not have been large stone hammers, wedges,
fire, etc.

As Gary has pointed out, it's a bitch to cut pure copper, even
with steel tools. Smart folks, like the Indians of those days
were (still are, BTW), would most likely have preferred to
extract the copper in more manageable sizes.



So mining involves exactly the type finds (and worse) I pointed to
with the URL.


I am aware of one piece of copper 17 ton of it (Yank ton presumably -
a short measure). It was found on the bottom of Lake Superior. I'm
also aware of another large find of several tons, but a VERY long way
underground in a modern mine. Neither kind of find was available to
the native people.


And nor would they have preferred them if they were available.
There is a huge chunk of copper still in a mine, which the
ancient Indians tried to extract, but appear to have given up as
a bad job. Still, they seemed to do OK without it.

BTW, what is your fascination with size here? It's not really
relevant.



Isn't it? Why else do claims of "more manageable sizes" get made? Also
mentions of "egg sized" etc... etc... indicating a contiguous piece of
pure copper of the required size. This right size lump message has run
right through the thread by the naysayers.


So mining appears to have *begun* where copper deposits were on
the surface. This makes sense, as there was also drift copper
(over a wider area than just the UP mining areas), and folks
early on seem to have selectively used lumps of copper that
needed no processing. While this might not have been an every
day event, it clearly was common enough to produce many of the
copper artifacts in the region.

As to mining the copper:

"They [Indians] dug pits in the ground and separated the copper

from the stone by hammering, by the use of wedges, and,

possibly, by the use of heat. Thousands of hammers have been
found in and about the old pits."


The claimed method is not fact - only assumption. The "fact" is the
finding a lot of "hammers". They are only proof of pounding or
hammering - which can mean crushing of rock containing the copper.


Yes, that too. Or do you imagine that the hammers were
single-purpose tools?



Indeed they are. A hammer is properly described as a "hand percussion
instrument" - a single purpose tool.


It seems that these folks picked the visible copper out of the
debitage after beating the bejesus out of the rock. That seems
reasonable to me, as there seems to have been quite enough such
copper available to make other methods of extraction unnecessary.

The dilemma you refer to does not seem to exist.

THAT is nonsense. I have provided you with a good example of the
nature of it. It isn't the first time I have done it either - and
haven't even had to use the same pictures.


Re-read (read?) what I wrote directly above the bit you went
off on.



"The dilemma you refer to does not seem to exist." - does exist - I
have provided evidence of it in the URL above.


Indian people
developed the technology they needed to extract the resource
they wanted.

Obviously, only you don't know what method they used. Nobody has
bothered to find out.


Ever heard of 'archaeology'? Or haven't *you* bothered to find
that out?



You are rejecting some methods, and still only recognise your own
unsubstantiated version that suits your view. You do not accept
crushing and melting to separate the copper from rubbish - to make it
into "more manageable sizes"!

http://www.iwaynet.net/~wdc/crucible.htm

"Neiburger says these bubbles are caused by hot gas in molten metal
and as such are solid evidence of copper melting and casting."

...not to mention other claims made on that site.


They may have developed copper casting technology
as well. Since smelting wasn't necessary, casting would have
been a stand-alone technology. It wasn't beyond the capacity of
the Indians of the upper Great Lakes; but it also wasn't necessary.


Then you can perhaps point to the huge piles of discarded copper that
was useless because it looked like that stuff in the first URL. There
have been vast amounts mined by the native people - where are the
rejected copper piles?


Some is still there.



Where?


I assume, but do not know, that modern
prospectors and miners would have processed such piles, as they
would probably have been a good source of copper for smelting.
Or do you think that respect for the past would have prevented
the modern copper industry from utilizing that resource?



I did anticipate this answer already :-)

Where is the evidence they did so? Remember "not knowing" means
"doesn't exist", in your methodology of argument. The ancient mining
sites are numerous - therefor scrap copper sites would be at least as
numerous - but more likely far more numerous as village sites don't
have them either. Therefor the recording of the use of these piles of
"copper rubbish" by early colonials is that much more likely to exist
in multiple places - IF it happened at all. Now all you have to do is
support your "what if" with facts or see it disappear - without even
so much as a puff of smoke.

"No large pieces of scrap copper were found, and this could be an
indication that the Cahokia copper craftsmen "had learned to smelt
copper scrap"." - ibid

"Perino noted that while it is known that many copper objects were
made at Cahokia, "nowhere in the area has anyone found any copper
scrap"." - ibid

A broader look for copper s/melting.

http://www.shef.ac.uk/assem/2/2dung2.html

(Review of book)
Early Metal Mining and Production - Edinburgh University Press 1995
ISBN 0 7486 0498 7
"The use of native copper in North America is explored in some detail
but the smelting and alloying technology of South America is barely
mentioned."

http://people.uncw.edu/simmonss/lamanai.htm

"Copper and bronze (copper-tin and copper-arsenic) began to arrive at
Lamanai during the 13th century AD. Provenience studies conducted by
Dr. Dorothy Hosler at the Massachusetts Institute of Technology
revealed that the copper used to produce many of these items was
obtained from West Mexican ore fields."

Note specially this:

http://people.uncw.edu/simmonss/P6030052.JPG

Where is the "obvious" evidence of it being cast?

There is a section on metals (pp.183-350) in the volume edited by
David A. Scott and Pieter Meyers, "Archaeometry of Pre-Columbian Sites
and Artifacts". What is says I have no idea

See this for an idea - not yet implemented?
http://www.socarchsci.org/ARK96.htm
LASER ION MASS SPECTROSCOPY AS A TOOL FOR ARCHAEOMETRY



If the copper is pure is not known because nobody has bothered to find
out.


And yet, they did. If you aren't going to read this thread any
better than you appear to have done in this sentence, why post?



Are you now claiming an extensive analysis of artefact has indeed been
done? I'm sure you would be eager to point to them -if they exist. So
where are they? As far as I know, only those few artefacts under
discussion have been analysed to any degree.


Silver does exist with/alongside/embedded in with copper in that
area - as are other minerals, including arsenic.


Sure. Copper artifacts have been found with just those
inclusions. However, silver isn't found in them as an alloy
(which might happen if the material were cast), but as
inclusions (which would happen if the copper-silver cobble were
worked by smithing).



How do you know that when the analysis hasn't been done?



You're funny, Seppo. Don't ever change.

Tom McDonald
  #109   Report Post  
Old July 2nd 04, 09:15 AM
Tom McDonald
 
Posts: n/a
Default Copper Casting In America (Trevelyan)

Seppo Renfors wrote:


Gary Coffman wrote:


snip

Do you have evidence of the existence of such villages in the area?



I posted information of this in a reply to Tom.


Seppo,

I don't recall that. Could you re-post it?



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.


Again, for the main time period and region under discussion
(Middle and Late Archaic), what evidence of villages do you
have? These folks were hunter-gatherers, and villages in the
sense we tend to use the term weren't typical. In addition, we
don't have a lot of habitation sites from this period. I'd
appreciate any evidence you have of same.

Tom McDonald

  #110   Report Post  
Old July 2nd 04, 10:49 AM
Gary Coffman
 
Posts: n/a
Default Copper Casting In America (Trevelyan)

On Fri, 02 Jul 2004 07:53:30 GMT, Seppo Renfors wrote:
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.


It is called silver brazing (or more commonly, but incorrectly, called
silver soldering). It is a common technique used to join pieces of
copper. Pressure is not required. A temperature in excess of 800F
is required for brazing to occur (by ASTM definition).

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.


Actually, it doesn't disagree with me. It says the copper
was carried in an aqueus solution from great depths
and deposited in the vents, fissures, and voids of the
iron bearing rocks above. The pertinent chemical
reaction involved is

CuSO4 + Fe(Metal) = FeSO4 + Cu (Metal)

If you were knowledgeable of the chemistry of copper, this
would have been obvious to you. If you had read any of the
many geochemical references in the links already provided
in this thread, it would have been spelled out for you in
excruciating detail.

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!


Again, I suggest you consult a good text on geochemistry. If you
feel such a text would be too daunting, then just look for descriptions
of the production of Ziment Copper, or how the leaching ponds at
Parys mountain operated. These processes mimic the natural
geochemical processes at work at Keweenaw.

Gary


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