I might still have the
IHC I payed with, most were VF-EF grade low dollar coins that had been cleaned to a bright orange look already. I do remember getting some incredible rainbow colors on them using the butane torch, but also ruined a few with scorch marks and bubbling on the surface from the extreme heat. I of course never made these to defraud or sell, it was after an
ANA summer seminar where Bob Campbell was first beginning to give his fantastic talk on the perils of AT on coins of the day. When I first heard this it was only a 30 minute "Bull Session" with a paper handout then a question and answer period that Bob did.
The NNP has his talk in a video:
https://nnp.wustl.edu/library/book/560383I've posted it before and I wish there was a newer talk recorded with better quality video, but it's still very pertinent information, Bob started doing this talk back in 1994 or maybe even earlier. I know there is also a copy of his 1994
ANA Convention talk on NNP as well.
Still a great video to watch for all collectors.

"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.
See my want page:
http://goccf.com/t/140440
Edited by westcoin
02/01/2021 3:59 pm