Anybody know what type of light and bulb the graders use to view the coins under?
Halogen lamps, I forget the brand, I have one that broke and is in a storage unit, never did get it repaired, back when I got it I worked at a coin shop and wholesale it was around $90.00 not exactly cheap I think the retail was $179.00 though with advances in lamp and bulb manufacturing technologies I'm sure they are a lot cheaper today. Many also use a good incandecent bulb from 70-150 watts as well.
Mark Feld (super guy) co-taught a grading class I attended at an ANA
Seminar Seminar, they absolutely do NOT use magnification when grading, only to verify parts of the coin, RPD, RPM, DDO
, etc. they do use a loupe on the surface or suspicious areas looking for putty filled ticks or other things that catch the eye. Most use a 5-7x power triplet. In fact he stressed that one should not use a loupe while grading. I have several friends that either are still grading or used to grade at the top TPG
's, none use a loupe upon initial examination for grade.
I thought that on 69-70 they used 5x.
Back when I was dealing in coins full time, this was before the modern coin grading at TPG
's so as to magnification on modern proofs I can't answer that, but I would believe they are checked under magnification.
"Buy the Book Before You Buy the Coin" - Aaron R. Feldman - "And read it" - Me 2013! ANA
Life Member #3288 in good standing since 1982, EAC Member #6202, NBS Member, 2¢ variety collector.