On Sat, 27 Jun 2009 09:52:18 -0700, in rec.crafts.jewelry Ted Frater
wrote:

Im not trying to argue with anyone, As I said Im confused ie not clear
if you follow, how the LaTene smiths made an alloy of copper and tin,
and were able to forge out an ingot to less thn a MM over such large
areas, based on the analysis ofthe original metal.

And that, of course, remains an interesting question. My owh suspicion is that
those smiths were using methods that differ from our own. Perhaps tools didn't
allow as efficient working, so metal wasn't being "moved" as quickly as with
modern hammers and anvils. That more delicate sort of work might stress an
alloy less, so even a brittle alloy might respond acceptably. Or perhaps there
is some specific temperature range one could forge the alloy at wherein it
becomes more workable. Or perhaps the assumption that it's forged from an ingot
isn't entirely correct. Maybe it was initially cast as a shape that's not too
far from the current form, meaing much less forging would be required. We make
lots of assumptions as to how it was made based on how WE would do it with
modern knowledge, modern tools and equipment, and our own education. That can
lead to errors or missed methods...

I'm rather guessing that spending lots of energy wondering what the exact alloy
is, and how alloys specifications are arrived at, may be looking at the wrong
end of the question. Instead of whether the answer is in incorrect assumptions
of what the alloy is, I'd take the stated analysis as given, and get back to
the "how" of how it was worked. The sophistication of the methods of ancient
smiths is easy to underestimate. These people were absolute experts at making
the alloys they had available and used, do the things they needed it to do. And
they could take however much time was needed. No doubt the range of alloys they
could choose from was much more limited, and they may have had to make do with
whatever they could get out of the ground, or not far from it. But they'd have
compensated with the technology of how they worked it.

Back in the late 70s, as part of a school trip to england, the group I was with
was taken through the British Museum's collection, and as part of that visit,
was given a private showing of the Sutton Ho treasure. I held a couple of those
items in my (gloved) hand, and was able to use a good loupe to examine the
things very closely. Now, I didn't have the experience I have now, but I wasn't
a total beginner either, with a good deal of lapidary experience in particular
under my belt at that time. To this day, the memories of those items still
amazes me, with the precision of the workmanship. Just how those folks were
able to shape all those garnet inlays as they did, not to mention work the metal
as well as they did, given the materials and technology they had available for
the task, still amazes me. Even with modern lapidary equipment, and modern
metalworking tools, duplicating that work would be well beyond the skills of
most modern jewelers, including me, I think.

So don't discount the simple factor of the skills of the people involved. Your
answer may be as straight forward as the notion that those folks were better at
working the specific metal alloy they had, than you, I, or your friend are.

Peter


Also I do follow everyones points about making alloys by weight,
my next step isto talk to the UK goldsmiths Co, of which im a member,who
run the Government assay offices here in the UK.
they will im sure put me right as to the question of alloys, after all
there assaying metal items all the time in their thousands.
Also so as not to leave any stone unturned ill also talk to Imperial
Metal industries at Whitton nr. Birmingham and ask them when they make
up an alloy , how do they do it? to achieve the specifications they
publish in their catalogues which ive here..
Then when ive their answers ill write it all up here.
You should all realise that I dont give up on something till im
satisfied with the answers. If i gave up on something as simple as this
what hope would there be for me as a metal craftsman on something
really difficult?