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oh you, Ea Nasir!
(lemmy.nz)
A community dedicated to making fun of Ea-Nasir, a Sumerian merchant circa 1750 BC, who sold exceptionally poor quality copper.
I worked at a pressure vessel manufacturer and we had what we called the "PMI gun"; basically a handheld spectrometer that would tell you the composition of whatever metal you pointed it at. They're relatively inexpensive from a business standpoint.