I know this has been discussed a lot on this forum and debated extensively, but what constitutes natural toning? If you stick a coin in an album that you know will tone a coin and leave it for several years, is still NT? I know that if you accelerate the process any i.e. smoking a coin is still AT,but where do you draw the line on purposeful NT. Is it months, years, decades? And does it count if it is with intent or if it was accidental? Then do we even rely on using the terms AT and NT anymore if it is such conjecture, or do we just go by eye appeal alone since on some cases it is so hard to tell? Sorry for the rant, just something I wanted to get an opinion on. Sent from my A463BG using Tapatalk
You are going to have people tell you that intent matters, and I will tell you the reason that it doesn't. Whenever you look at a coin, the only information you have, is the appearance of the coin. There is absolutely no way to determine the intent of the previous owner. Therefore, you must judge the originality of the toning by comparing it to the typical color schemes and patterns found on that particular type of coin. Use indicators of natural and artificial toning to help make your determination. Some indicators would be proper color progressions, toning correspondence, elevation chromatics, pull away toning etc. As a starter, please read the article linked below by Jason, Physics-fan3.14. What You Need to Know About: The Science of Toning And to answer your question, the TPGs really don't use NT or AT. They mostly use MA (market acceptable) and QT (questionably toned). Toning is not a black and white determination. It is better to think of it as a sliding scale with QT (AT) to the far left, and MA (NT) on the far right with the middle representing the coins that are difficult to classify. I once made a visual representation of such a scale using Jefferson Nickels (see below). I hoped this helped answer your question. Paul
Toning is tricky. I would venture to say 80-90% of all rainbow toners are artificially induced in one way or another, regardless of whether the slabbing services accept and slab them or not. About a decade or two ago before the rainbow toning craze hit, and everyone wanted shinny coins, you'd be hard pressed to find too many rainbow toned coins, or many toned coins for that matter...now a days they seem to be a dime a dozen. As long as it doesn't look like a rainbow threw up all over the coin, it may still be market acceptable though, even if human hands aided in the process. Look, the reality is that most of your slabbed coins have been cleaned anyways at some point in the past...just done in a way which didn't really harm the coin. There are people here who know how to do that. And I bet you there are people here who can also tone those coins in a way that wouldn't raise a red flag at a TPG. I bet you when the rainbow toning phase passes, you'll start to see shinny coins making a huge comeback as rainbow toners become shinny again thanks to those with the know how. I personally don't care about whether the toning is aided or not as I deal with ancients, and we don't obsess over stuff like that, but if it helps I'm pretty sure this is one is naturally rainbow from sitting in a sulfur rich envelope since the early 1970s when it last went on sale to the public.This is what I would expect to see after 40+ years in an envelope, and not those psychedelic colors you see on Ebay on a bunch of US coins. .C. Vibius C.f. Pansa AR Denarius Attribution: Crawford 342/5b; Vibia 1b; Syd 684b Date: 90 BC Obverse: PANSA behind laureate head of Apollo right, S before Reverse: Minerva driving galloping quadriga right, C•VIBIVS•C•F in exergue Size: 18.83 mm Weight: 4.03 grams And this is what I would expect to see in a coin that hasn't had any "professional cleaning" in over 100 years. Not saying some coins can't remain relatively shinny if stored in certain conditions, but those conditions were not too common in the past given the rudimentary climate control, sulfur in storage material, etc. and other aspects of the hobby at the turn of the century when most coins would have been stored in cabinets or envelopes (mostly homemade envelopes) by collectors. M. Cipius M. F. AR Denarius 16mm. 3.90g. Rome Mint Helmeted head of Roma, r.; X behind. M. CIPI. M. F. Victory in biga, r.; rudder below horses; In ex.: ROMA Crawford 289/1; RSC Cipia 1 But with the cleaning know-how that I know some people here also know, I bet you I can make both of them shinny without leaving any evidence of cleaning. Not that I will, as I honestly don't care about that. I could also rainbow tone them afterwards if I felt like it...which I don't care to do, but again, the point is that the knowledge is there. It can be done.
There is no such thing as NT/AT. Toning is either market acceptable or it isn't. It's really that simple.
