Quote:
Originally Posted by swarmee
There is, but if it's your card, are you willing to have them take a piece of the signature off the card to run it through a mass spectrometer? I'm not sure there is a non-invasive way to test it.
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There are non- invasive spectrograph machines. Mostly used for metals. They will give an accurate reading of the elements in the ink, but then you need to know what inks were made of in the past and what they're made of now. Some ink formulas have probably remained unchanged since the 70's.
Those machines are slowly becoming used for stamps, and a few of the things that everyone "knew" have been proven wrong. Like the brown inks for the 1847 stamps were "known" to be pigmented with rust. Except the recent spectrograph showed exactly 0% iron.....