.001 scales are generally used for laboratories, serious powder/gun re-loaders, and gems/diamonds, they will almost without exception have a cover over them to stop any air disturbances from affecting the weighing of materials (per-moxking), they are really way to accurate for anything needed in numismatics, if you need you could always use the water displacement method to figure out density along with a digital scale accurate to .01 grams.
"Buy the Book Before You Buy the Coin" - Aaron R. Feldman - "And read it" - Me 2013!
ANA Life Member #3288 in good standing since 1981, ANS, Early American Coppers Member (EAC), Colonial Coin Collectors Club member (C4), Conder Token Collector Club member (CTCC), Civil War Token Society (CWTS) member, Liberty Seated Collectors Club (LSCC) & Numismatic Bibliomania Society member (NBS), USMex, Member in good standing, 2¢ variety collector.
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