From the book German Medal Makers and Their Marks, Second Edition, Mark Woods
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Hi John,
This is an area I've been looking into as well, albeit only with internet research and not physical metallurgical texts. This is a very confusing topic because collectors and dealers use the terms in a variety of different and often conflicting ways.
That's a good table but I would clarify a few points:
1) Buntmetall (literally "coloured metal") is a German word and should have two L's at the end. In modern chemistry, it is any non-ferrous metal whose salt solutions produce various lovely bright colours (hence the term "Buntmetall" or "Coloured Metal") but this is NOT the way the term was used historically or in collecting.
Historically, in Material Science terminology which is now considered obsolete but applies still to the descriptions of historical artifacts, "Buntmetalle" or Coloured Metals specifically referred to copper-based alloys, in contrast to "Weissmetalle" or White metals, and the "Schwarzmetalle" or Black metals (ferrous-based).
2) Zamac (or Zamak) is an acronym for Zinc, Aluminum, Magnesium and Copper (Kupfer) but confusingly doesn't have to have Magnesium and Copper in it. It refers to a family of alloys which must be predominantly zinc and contain 4% aluminum, and the commonest type is as Mark Woods states just zinc (96%) and aluminum (4%). Therefore, although the author included it under the "Buntmetalle", technically Zamac of this type is not really a "Buntmetall" since it's not copper-based and in fact is a "Weissmetall".
However, dealers will still often describe zinc-based badges as "Buntmetall" which is technically incorrect and very misleading!
3) "Neusilber" is spelt wrong in the table having left out the 'u'. Neusilber (aka "new silver", "German silver", "nickel silver") actually has no silver in it, and is typically 60% copper, 20% zinc and 20% nickel but can vary in the various proportions of these 3 constituents. Since it's copper-based it's a "Buntmetall" although it's silver-coloured.
4) "Bloom", or hydrozincite, referred to in the table, is the same as zinc pest, the corrosive incrustation of hydrous carbonate, that occurs due to the reaction with the lead impurities in the zinc.
Best regards,
---Norm -
Hello Norm,
I want to send an email to the author so he can update his errata sheet, however, I want to be careful in that what we tell him is correct. This is the entire page vice just the chart and from what you are saying, beyond the spelling mistakes and the misplacement of zamac, there are no errors?
I also do think that "bloom" should have been explained as I thought it might include bubbling as well as zinc pest--I am not sure if that is technically the same, but I do not think so. Both of course are chemical reactions within the metals, but bubbling perhaps should have its own technical or chemical word in addition to pest.
JohnComment
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Is it true he still has Wiedmann listed as Wernstein, or has that been changed?Comment
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In the book he states it is under discussion, but in his errata sheet he has it as Wiedmann. See attached scan.
JohnComment
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Hi guys,
Along with all Norm's points, I would also point out that Cupal is not really an alloy of copper and aluminum. An alloy is a mixture of these metals where they are heated up and melted together to form a new, homogenious material.
However, Cupal is not an alloy. It is more like a sandwich, where a thin copper layer was simply pressed on top of a thick layer of aluminum. These were pressed together (just like plywood). Looking at Cupal from the side, you can see the 2 different layers pretty distinctly.
Looks to be an excellent book, and I hope someone is selling it at the MAX.
TomIf it doesn't have a hinge and catch, I'm not interested......well, maybe a littleNew Book - The German Close Combat Clasp of World War II
[/SIGPIC][/SIGPIC]Available Now - tmdurante@gmail.com
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From the book, I think it is saying what Tom has just said. This follows on the pages after the ones posted above.
JohnComment
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Hi John,
Yes, he describes it much better on that last page you just posted. He even mentions in the text that Cupal is NOT an alloy, so he must have just had a mistake in terminology on that first page you posted. An easy fix for sure and a mistake that only the nerdiest of collectors like us will probably notice anyway
TomIf it doesn't have a hinge and catch, I'm not interested......well, maybe a littleNew Book - The German Close Combat Clasp of World War II
[/SIGPIC][/SIGPIC]Available Now - tmdurante@gmail.com
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Hi John,Originally posted by John Robinson View Post
The location of Zamac in the table is controversial, since technically it should be in the zinc group, but by dealers is commonly mis-placed as a "Buntmetall". So it depends on whether one wants to be accurate or perpetuate a commonly used misconception...
At the very least Zamac should be referred to a "Zinc/Alum" alloy rather than "Alum/Zinc" alloy since it's mostly zinc.
I agree that bubbling is different from zinc pest. Although I don't know the exact chemical process in bubbling, I believe its a process that produces gas which causes the bubbling under a finish or plating on the zinc, in contrast to zinc pest which is a crystalline corrosion, hydrozincite Zn5(CO3)2(OH)6, on air/water exposed zinc/lead surfaces.
Cheers.
---NormComment
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But that's a good point Tom. In the table he shouldn't say "copper/alum alloy" but rather just "copper/alum" and "see text". Call me a nerd, but better to be correct.Originally posted by Thomas Durante View PostHi John,
Yes, he describes it much better on that last page you just posted. He even mentions in the text that Cupal is NOT an alloy, so he must have just had a mistake in terminology on that first page you posted. An easy fix for sure and a mistake that only the nerdiest of collectors like us will probably notice anyway
Tom
---NormComment
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I agree and that is also why I think authors should use errata sheets. Impossible to write any book on this subject (TR militaria) and be 100% correct in everything.
It is a very exacting hobby these days, no getting around it.
Using the internet, authors can get feedback quickly which was never possible before. So they can update errata sheets for books not sold or post the errata sheet I guess with their publisher's website. Or, when the next edition comes out, they can make the changes there too.
Not a perfect system but I think authors are in a way fortunate to have the feedback.
It is like what I said in the book review thread, somewhere authors copied a list of Prasidialkanzlei numbers and names and misspelled the maker Tham (101 and 103) as "Tam" and that has been perpetuated forever.
Small detail but this hobby only can improve when these details are recognized and mentioned.
JohnComment
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Updated errata sheet just received.
JohnComment
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Here's an updated suggestion for the table of metals used in award manufacture.
Best regards,
---NormComment
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