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Can Science help distinguish replica, metal-made collectables?

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  • Can Science help distinguish replica, metal-made collectables?

    Apologies for the long post.

    I would like to present to fellow collectors, an experiment I undertook at our local university this week. The purpose was two-fold; 1) to establish a “proof-of-concept” for using SEM-EDX to adequately identify the elemental composition of a collectable, metal insignia and, 2) to use this same technique to try to determine that, if by looking at the elemental composition, one might be able to determine replica or “fake” items within the vast field of collectables. To demonstrate the later, I choose to look at one of my collecting interests, the CAF (Canadian Air Force) insignia circa 1920-1924. They are uncommon enough that one generally doesn’t come across a large selection so collectors may only see these in isolation at shows, dealer’s stores, online or auction houses and at times, it can be very difficult to know if an item is truly an authentic, original, period piece or not. As we all know, it’s getting harder as the fakes and fakers get better.

    The Zeiss-EVO SEM-EDX (Scanning Electron Microscope with Energy Dispersive X-ray) is an instrument which, beyond incredible imaging capabilities, allows materials research and analysis which can provide quantitative*, elemental identification. In my case, I was primarily interested in the later for my insignia not the imaging capabilities so coating of the samples wasn’t required and the technique is non-destructive; i.e., you get your stuff back intact and unaltered! The scientist who ran this instrument during my session was very knowledgeable, helpful and pro-active with suggestions (thanks Nathan).
    Over the last few years, I have picked up several examples of the enlisted, Type 2 (with motto) versions of CAF collars which have had an unexpected crown for the issue. Unusual in the sense that it has the larger void shape normally reserved for Officer’s more complex, multi-component badges. Enlisted versions have a small void in the crown and are basically two-piece; a CAF monogram fitted over a die stamped body and fastened in place by a pin through the center then riveted to the back of the badge. Could there have been errors during assembly, some variant that hadn’t been reported or were they modern replicas?
    The first two images below illustrate an original collar on the left and the questionable copy on the right. I’ve highlighted a few differences to note between the two. The lack of detail on the reverse of the replica is a give-away – if you know what to expect. Four additional variations are shown, each with a slightly different finish but by using the SEM-EDX, they show a wide variety of elemental compositions. The top left example is very interesting as it is mainly an alloy of tin with some lead. The finish is from an aluminum powder coating or paint and there is a high percentage of Cd, Cadmium in the piece, a toxic compound often found in off-shore costume jewelry. The top right example is basically made from a 50/50 solder of Pb-Sn (lead-tin) composition.

    The original enlisted versions of cap and collar CAF insignia have an elemental composition of primarily Copper, Nickle and Zinc often called “German” metal. Based on initial measurements of several period pieces of CAF cap and collars, they all exhibit similar ratios in their major elemental components.
    To illustrate the EVO’s output, a rough graph and semi-normalized elemental weight% values of one replica piece is illustrated. Further calculations and assumptions to normalize all readings were required to give a final “quantitative” estimate of the various elements present. The microscope doesn’t analyze the entire badge; only a very small, sub mm portion selected by the user and chosen to be representative of the object under study. The area is selected to be “clean” from surface contaminants; oxidation, sulfonation, the initial organic lacquer applied to these insignia to help preserve luster, grease and dirt, etc.

    One of many interesting side observations that came out of this study was that at least some original enlisted CAF monograms had a trace of surface silver plating presumably to highlight that component. The low res SEM image shows the valleys and ridges on the top of the “A” in the CAF monogram. Visually through the SEM eye, one can observe a difference in the composition as demonstrated by a shade and texture variation and further borne out in the analysis at the points of the barely visible, green, overlaid numbers 2 and 3. The lower recessed layer contained regions indicated at over 95% silver while the majority of the monogram was the same composition as the main insignia. This suggests a very light silver coating on the NCO monograms which has worn off on the higher relief regions; more sampling of different pieces would be required to confirm this as a general statement. Also noted in passing is that the monogram pin is composed of 100% copper, probably because it was easy to solder onto the monogram and easy to rivet to the body of the badge.
    I was also able to briefly look at some replica CAF pilots wings (I have four, clearly different replica variations but all possibly formed from the exact same duplicated die). This will be discussed perhaps in a submission to the MCCoC Journal down the road.

    Other collectable areas such as fine art, stamps and sports memorabilia have respected recognized experts, technology and organizations where one can send their rare and valuable items for authentication and certification. Perhaps it’s time our field offered such a service too? Maybe this instrument will play a role in that in the future.

    Regards,
    Wayne Logus
    Attached Files

  • #2
    To quote a famous actor, "Fascinating".
    Res ipsa loquitur

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    • #3
      "Cor".

      Rob

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      • #4
        Wot Bill said!

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        • #5
          I actually found this to be extremely interesting and well explained.....but then again I am a Chemist so I suppose I would find it interesting. A great read and fascinating stuff.
          Cheers
          James
          All of the darkness in the world can never extinguish the light of one candle.

          Comment


          • #6
            Great read, one wonders what cost 👌👌

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            • #7
              Great read, one wonders what cost 👌👌

              Hi Drmiggy:
              A valid and important question. No absolute answer. However, a local coin and gold buyer has a much simplified version, without microscope, which gives a single reading. It is designed and calibrated for silver and gold, not other metals in his case but he has done several readings for free for me. One can buy calibration elements for other metals. I think those entire units run around 20,000?

              The SEM-EDX is clearly high end and designed for researchers. It will most likely only be found on large University campuses or sophisticated Materials Testing labs. The unit I had access to had three levels of charges; one for students in the department, one for other campus researchers and one for business or industrial applications.

              "Individual results may vary around the world, I'm sure". It will depend on the exact device too. The largest portion of time goes to having the machine pump down a vacuum; some units are faster than others. We were able to look at about 6 pieces an hour and in my specific case, rates were $65/hr. Also, with the smaller collars, we were able to put 3 pieces in at a time thus saving time in the vacuum process.

              Hope this helps. It's not prohibitive.

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              • #8
                Very interesting but whatever happened to peoples skills built up over the years from experience and personal research?
                What do I know that no other collector knows and a machine can never tell you?
                Researcher 39th Battalion, Kokoda campaign and Australian sappers.

                Comment


                • #9
                  I agree Akiko, there’s no more valuable teacher than experience. That is why we buy reference books, consult specialists and use internet Forms to obtain and share knowledge. The device in question is just another tool; it adds information, accuracy and detail that one possibly didn’t have before. It serves as one component of many that one can use in making an educated, rational and informed decision about an object.

                  As we have seen many times on the Forum, even experts may disagree given the same images and information. Further, in some cases and given all the facts, there just may not be enough data to reach a definitive conclusion.

                  What harm can there be in providing a new level and depth of knowledge about an item? Is it generally not better to have a colour picture rather than one in Black and White or dimensions rather than descriptors such a “big”?

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                  • #10
                    Hello Wayne,
                    Damned impressive! In many respects it parallels the well established use of gas chromatography, mass spectrometry, and nuclear magnetic resonance spectrometry, in the precise identification of unidentified clandestine chemical warfare agents. Readily admit experience weighs heavily, and certainly not to be disregarded as a major factor. However experience combined with forensic science elevates analysis to an evidentiary level of proof. With the recently rising acquisition price of some badges, this is an additional significant weapon in the arsenal against counterfeiters. Gentlemen you are to be reminded that it's the 21st Century. Well done!

                    ArnhemJim not Arnhem Jim
                    Arizona Territory
                    Last edited by Arnhem Jim; 03-05-19, 09:40 PM.

                    Comment


                    • #11
                      Can this be used to discern the age of a badge?

                      I can see that comparing proportions of metals in an alloy could suggest that they weren't made from the same sheet of "gilding metal" which is still available, but its possible that the percentages in the raw materials were actually less consistent then than they are today.

                      Rob

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                      • #12
                        Here is a similar themed thread from back in 2011.

                        Rob

                        https://www.britishbadgeforum.com/fo...hlight=nuclear

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                        • #13
                          Originally posted by zorgon View Post
                          I agree Akiko, there’s no more valuable teacher than experience. That is why we buy reference books, consult specialists and use internet Forms to obtain and share knowledge. The device in question is just another tool; it adds information, accuracy and detail that one possibly didn’t have before. It serves as one component of many that one can use in making an educated, rational and informed decision about an object.
                          I'm not dismissing it as a tool only highlighting that human knowledge also comes into the equation. Would I use it? On some badges yes to get metal composition etc., but not to see if something is original.
                          As we have seen many times on the Forum, even experts may disagree given the same images and information. Further, in some cases and given all the facts, there just may not be enough data to reach a definitive conclusion.
                          There'll always be 'experts' disagree on something or other but I agree with you on this point. As I said it's a very interesting post.
                          Researcher 39th Battalion, Kokoda campaign and Australian sappers.

                          Comment


                          • #14
                            Originally posted by zorgon View Post
                            Great read, one wonders what cost 👌👌

                            Hi Drmiggy:
                            A valid and important question. No absolute answer. However, a local coin and gold buyer has a much simplified version, without microscope, which gives a single reading. It is designed and calibrated for silver and gold, not other metals in his case but he has done several readings for free for me. One can buy calibration elements for other metals. I think those entire units run around 20,000?

                            The SEM-EDX is clearly high end and designed for researchers. It will most likely only be found on large University campuses or sophisticated Materials Testing labs. The unit I had access to had three levels of charges; one for students in the department, one for other campus researchers and one for business or industrial applications.

                            "Individual results may vary around the world, I'm sure". It will depend on the exact device too. The largest portion of time goes to having the machine pump down a vacuum; some units are faster than others. We were able to look at about 6 pieces an hour and in my specific case, rates were $65/hr. Also, with the smaller collars, we were able to put 3 pieces in at a time thus saving time in the vacuum process.

                            Hope this helps. It's not prohibitive.
                            It actually seems reasonable, especially for those high end badges that can cause debate. I would quite willingly pay an extra tenner and be sure I have an original. Yes experience does come into the equation, but experience with evidence, that’s one step further. Bring it on. Thanks

                            Comment


                            • #15
                              Rob Miller asked:
                              "Can this be used to discern the age of a badge?"

                              I'm not an expert or probably even qualified to answer this Rob but I would say "no" at least not directly. I would speculate that there are tell-tale "fingerprint' molecular signatures that can, in some cases, be extrapolated from the results that might be able to narrow down the period the object was cast. I mentioned that some scans of replica pieces detected Cadmium (Cd). I would speculate that it is highly unlikely that any original insignia pre WWII would contain Cd as a contaminant. It’s a sad and ironic reflection of our time and our throw-away society, that our waste, in this case probably reformed from NiCd batteries, can find their way back to us in these recycled insignia.

                              The dating aspect is best left answered by someone who specializes in this type of analysis and has the experience and background in interpreting metal composition. Before this becomes anywhere close to a routine test, one would need a large library of results of known original pieces to establish “normal” ranges; a labour of love by someone with near full time access to such a machine.

                              It has been asked if there might be a technique for analyzing radioactivity levels in objects to give, at least, pre-post Nuclear weapon development. That discussion should be addressed in a different thread I think but I have used an extremely sensitive hyper-pure germanium gamma spectrometer for looking at trace amounts of gamma radiation to determine the source of initial radiation – not exactly the same thing but the tool itself would be the device to use I think. Another little trial study to be conducted perhaps.
                              https://forum.keypublishing.com/foru...m-abroad/page4

                              Also, thanks Rob for that earlier 2011 BBF link by mooke07. I hadn’t seen that; excellent presentation.

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