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<p>[QUOTE=&quot;TypeCoin971793, post: 3819093, member: 78244&quot;]I did the XRF test today, and I am officially concluding that the original XRF data does not remotely correspond to the metallic composition of the coin. That favors very strongly with the authenticity of the piece. Results are in the discussion below.</p><p><br /></p><p><br /></p><p><br /></p><p>The device I used had an X-Ray tube that measured about 15mm x 15mm. That meant that the entire 15mm x 15mm area got analyzed.</p><p><br /></p><p><br /></p><p><br /></p><p>The material in the patina and the metal of the coin are most definitely not the same. When I analyzed the cleared area on the obverse, the sample area included a lot of the surrounding patina crust. The results for this area were:</p><p><br /></p><p>Cu 34.34%</p><p>Pb 43.96%</p><p>Sn 13.55%</p><p>Fe 0.66%</p><p>Ti 5.46% (yes, Titanium!)</p><p><br /></p><p>The X-Rays from the transmitter can only excite atoms a few microns into the surface and read the electromagnetic spectra they give off. This means that all patina in the analysis region would have blocked analysis of the metal underneath, so this was a very inaccurate sampling of the metallic composition of the knife. The significant presence of titanium (!) was likely from titanium oxide deposits on the coin, meaning that the patina was severely skewing the results.</p><p><br /></p><p><br /></p><p><br /></p><p>After the above run, I decided to analyze the handle area of the reverse as it was the most-cleared area of the coin (though there was still a noticeable amount of deposits left behind). The width of the handle was sufficient to cover the entirety of the x-ray tube. Two tests were run on two areas of the handle, producing the following results:</p><p><br /></p><p>Run #2:</p><p><br /></p><p>Cu 53.53%</p><p>Pb 20.58%</p><p>Sn 28.48%</p><p>Fe 0.56%</p><p>Ti 0.23%</p><p><br /></p><p>Run #3:</p><p><br /></p><p>Cu 54.61%</p><p>Pb 19.47%</p><p>Sn 20.19%</p><p>Fe 1.05%</p><p>Ti 0.24%</p><p><br /></p><p>This shows that the coin is mostly copper and not mostly lead, like I had already concluded above. However, JiMo knives are typically 65-70% copper, with 3-character Qi knives typically being 50-55% copper. So what gives?</p><p><br /></p><p>As stated previously, the tested areas of the handle were not perfectly cleared, so there was still a noticeable amount of patina left behind from the aggressive cleaning. As demonstrated in the first test, the patina contains an abnormally-high concentration of lead, so this would skew the relative numbers of the other elements down. The ratio of tin to copper in the first test was also abnormally high, which suggests that there might also be a high concentration of tin in the patina as well. adjusting both of these values down would result in a metallic composition that would be in line with genuine JiMo knives.</p><p><br /></p><p>I stand by my original conclusion that this coin is authentic.</p><p><br /></p><p>Thoughts [USER=87271]@AnYangMan[/USER] ?[/QUOTE]</p><p><br /></p>

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