Some are obvious with colors that are never seen on natural toned coins. Some are not definite either way. This linked thread has some of the science behind it.
If the toning appears to be etched into the coin surface it could be AT. I've found over the past 25+ years original toning looks like oil on water. The toning seems to float on the surface. Reach out to Mark Feld, he might have some insight on what to look for and/or share on these boards.
Additionally, there is a consistent toning patterns to coins. Seek out a coin color spectrum. It will assist in the color movement across the coin.
"If there are no dogs in Heaven, then when I die I want to go where they went." Will Rogers
Not easily described, unfortunately. Looking at a lot of slabbed coins, particularly classic vs modern should be instructive. See if you can attend a show to examine various graded coins. The CoinFacts site with pictures can help, but time spent with coins are the best way to train your eye.
@Zoins has a reverse toned Morgan dollar (detailed graded) that is clearly artificially toned. Perhaps if he sees this message, he'll post it for you. Yet, there are many naturally toned Morgans that received their toning from sulfur infused cloth bags. Such toners often produce outrageously beautiful colors.
Seated Half Society member #38 "Got a flaming heart, can't get my fill"
@davewesen said:
Some are obvious with colors that are never seen on natural toned coins. Some are not definite either way. This linked thread has some of the science behind it.
The only thing my read was there are many color spectrum's and how to weigh their density for resale. Does this method help in the AT or NT question.
Reason why.
This coin below seems, too exact, in the placement of the color hues shown in photo.
In hand shows it much better , more pastel looking. Hey, not by me. Given to me as change while delivering a pizza.
.
** If the toning appears to be etched into the coin surface it could be AT.** I've found over the past 25+ years original toning looks like oil on water. The toning seems to float on the surface. Reach out to Mark Feld, he might have some insight on what to look for and/or share on these boards.
Additionally, there is a consistent toning patterns to coins. Seek out a coin color spectrum. It will assist in the color movement across the coin.
I don't think this is correct. A natural toning progression gets darker and the darker it gets, the more the surface is destroyed (etched).
@davewesen said:
Some are obvious with colors that are never seen on natural toned coins. Some are not definite either way. This linked thread has some of the science behind it.
The only thing my read was there are many color spectrum's and how to weigh their density for resale. Does this method help in the AT or NT question.
Reason why.
This coin below seems, too exact, in the placement of the color hues shown in photo.
In hand shows it much better , more pastel looking. Hey, not by me. Given to me as change while delivering a pizza.
.
This is a shock! Previously, I've only seen the magnified, colorful, corroded, images. I like the improvement.
“How Do I Tell The Difference In Real And Artificial Toning
Does Anyone Have Any Thoughts?
>
There’s far from universal agreement regarding what constitutes “natural” or “artificial” toning. And even among those who are in agreement, sometimes, even the experts can’t tell the difference.
Still, in order to try to learn how to be able to make such distinctions, I recommend looking at very large quantities of coins and coin images that the major grading companies have labeled as “questionable” or “artificial ” toning or “recolored”. In addition to that, if you have the opportunity to sit down with a knowledgeable numismatist who’s willing to show you examples and discuss the differences and what to look for, go for it.
Mark Feld* of Heritage Auctions*Unless otherwise noted, my posts here represent my personal opinions.
start by dismissing the notions of natural and artificial. All toning originates from a chemical reaction brought on by a combination of exposure and temperatures. Trying to ascertain the historical combo that brought that about is often a fools errand and an exercise in imagination. Toning fans will always have a "story" about origin such as a humid attic in a hurricane while pigeons flew nearby to explain what they consider attractive but atypical patterns.
The real standard is Market Acceptable or not market acceptable which is easier to gauge based on conforming appearances compared to other examples and then passed though the prism of eye appeal. Attractive coins simply find a easier time being embraced by the market even when questionable. One of the tells is time paints in layers. If the color is flatly applied it is most often a rushed/accelerated process which is more often than not rejected by the market
@4Redisin said:
I don't think this is correct. A natural toning progression gets darker and the darker it gets, the more the surface is destroyed (etched).
at least toned pure silver reacted with oxygen will go darker and darker. obviously at some point is stops because the oxide forms a protective layer to prevent further reaction
as far as rainbows, we're looking at somewhere close to 100 years on these things. and, for the blast white, they're stable too
if the rainbows get "darker" they'd need someway for oxygen to break through the existing toning layer. and the colors likely wouldn't get more vivid without the same chemicals present that formed the rainbow
How to tell the difference between real and artificial toning is one of those questions that really can’t be answered correctly 100% of the time, and anyone that tells you otherwise isn’t being honest. The best that the top Grading Services, dealers, collectors, etc. are able to agree on is a compromise often referred to as Market Acceptable.
Based on personal experience each of us forms an opinion.
"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety," --- Benjamin Franklin
When I send a coin in to be graded and it has some toning to it-they send it back as AT and say thanks for your donation. Really, I have problems trying to tell the difference and I think I'm 1 for 20. I wish I could deduct the donation off my taxes.
🤑🥵😮💨
USN & USAF retired 1971-1993
Successful Transactions with more than 100 Members
What they call toning now - Tarnish is Tarnish IMo. It is external surface damage to the coin whether environmental or artificial. I stay away from tarnished coins what they call nowadays nt or at lol. If somebody wants pay more for what they think is nt it’s their money. But at my table…..just not a big fan of tarnish.
Overtime as tarnish oxidizes with the atmosphere it will get darker. Truly original is what the coin looked like GEM BU off the mint press.
@JWP said:
When I send a coin in to be graded and it has some toning to it-they send it back as AT and say thanks for your donation. Really, I have problems trying to tell the difference and I think I'm 1 for 20. I wish I could deduct the donation off my taxes.
🤑🥵😮💨
Just start an llc and you can.
Paper money eventually returns to its intrinsic value. Zero. Voltaire. Ebay coinbowlllc
If you want to become an expert on toning, you will also want to gain an understanding of what caused the toning. Different coins and different series have very different attributes when it comes to toning. For example, the vast majority of toned Morgan dollars toned as a result of exposure to sulfur and other chemicals in the mint bags. Although there is a very wide range of types and colors of mint bag toning on Morgans, I think you could classify them into a half a dozen key categories. The various classic commemoratives often have distinctive toning related to methods of manufacture and distribution. For example, the toning will vary whether it is a Columbian or a Columbia or a Vancouver or an Antietam, but each of these has describable “typical” toning. Mint set toning on sets sold from 1947-1958 is usually distinctive, and I think people who have looked through many of them could describe different attributes by year. Then there is album toning or end roll toning or toning imparted by various tissue papers. It’s a fascinating topic and it is relevant to identifying AT versus NT. The doctors of course may try to imitate these historical toning processes, and some are very adept at it, but you are still in a better position if you know what to expect, for example on a 1926 Oregon Trail or a 1958 Franklin.
Comments
Some are obvious with colors that are never seen on natural toned coins. Some are not definite either way. This linked thread has some of the science behind it.
https://forums.collectors.com/discussion/708296/towards-an-understanding-of-the-color-progression-on-toned-coins/p1
For the coins you are interested in (say toned MS Morgans) I would look at Trueview photos in Coinfacts to get a “feel” for what is market acceptable.
"Flip a coin"
Sometimes it is super obvious, other times it is a gut feeling and not so obvious otherwise.
I've been told I tolerate fools poorly...that may explain things if I have a problem with you. Current ebay items - Nothing at the moment
Just a thought:
If the toning appears to be etched into the coin surface it could be AT. I've found over the past 25+ years original toning looks like oil on water. The toning seems to float on the surface. Reach out to Mark Feld, he might have some insight on what to look for and/or share on these boards.
Additionally, there is a consistent toning patterns to coins. Seek out a coin color spectrum. It will assist in the color movement across the coin.
There was a great ANA video on this way back. It would be great to find.
Honestly, it comes down to experience. Seeing a lot of certified examples of both NT and AT coins, you start to notice the difference in their "look".
Not easily described, unfortunately. Looking at a lot of slabbed coins, particularly classic vs modern should be instructive. See if you can attend a show to examine various graded coins. The CoinFacts site with pictures can help, but time spent with coins are the best way to train your eye.
@Zoins has a reverse toned Morgan dollar (detailed graded) that is clearly artificially toned. Perhaps if he sees this message, he'll post it for you. Yet, there are many naturally toned Morgans that received their toning from sulfur infused cloth bags. Such toners often produce outrageously beautiful colors.
"Got a flaming heart, can't get my fill"
The only thing my read was there are many color spectrum's and how to weigh their density for resale. Does this method help in the AT or NT question.

Reason why.
This coin below seems, too exact, in the placement of the color hues shown in photo.
In hand shows it much better , more pastel looking. Hey, not by me. Given to me as change while delivering a pizza.
.
I don't think this is correct. A natural toning progression gets darker and the darker it gets, the more the surface is destroyed (etched).
This is a shock! Previously, I've only seen the magnified, colorful, corroded, images. I like the improvement.
Follow the money, you'll get your answer.
Disclaimer: I'm not a dealer, trader, grader, investor or professional numismatist. I'm just a hobbyist. (To protect me but mostly you! 🤣 )
“How Do I Tell The Difference In Real And Artificial Toning
>
There’s far from universal agreement regarding what constitutes “natural” or “artificial” toning. And even among those who are in agreement, sometimes, even the experts can’t tell the difference.
Still, in order to try to learn how to be able to make such distinctions, I recommend looking at very large quantities of coins and coin images that the major grading companies have labeled as “questionable” or “artificial ” toning or “recolored”. In addition to that, if you have the opportunity to sit down with a knowledgeable numismatist who’s willing to show you examples and discuss the differences and what to look for, go for it.
Mark Feld* of Heritage Auctions*Unless otherwise noted, my posts here represent my personal opinions.
start by dismissing the notions of natural and artificial. All toning originates from a chemical reaction brought on by a combination of exposure and temperatures. Trying to ascertain the historical combo that brought that about is often a fools errand and an exercise in imagination. Toning fans will always have a "story" about origin such as a humid attic in a hurricane while pigeons flew nearby to explain what they consider attractive but atypical patterns.
The real standard is Market Acceptable or not market acceptable which is easier to gauge based on conforming appearances compared to other examples and then passed though the prism of eye appeal. Attractive coins simply find a easier time being embraced by the market even when questionable. One of the tells is time paints in layers. If the color is flatly applied it is most often a rushed/accelerated process which is more often than not rejected by the market
11.5$ Southern Dollars, The little “Big Easy” set
at least toned pure silver reacted with oxygen will go darker and darker. obviously at some point is stops because the oxide forms a protective layer to prevent further reaction
as far as rainbows, we're looking at somewhere close to 100 years on these things. and, for the blast white, they're stable too
if the rainbows get "darker" they'd need someway for oxygen to break through the existing toning layer. and the colors likely wouldn't get more vivid without the same chemicals present that formed the rainbow
How to tell the difference between real and artificial toning is one of those questions that really can’t be answered correctly 100% of the time, and anyone that tells you otherwise isn’t being honest. The best that the top Grading Services, dealers, collectors, etc. are able to agree on is a compromise often referred to as Market Acceptable.
Based on personal experience each of us forms an opinion.
"Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety," --- Benjamin Franklin
When I send a coin in to be graded and it has some toning to it-they send it back as AT and say thanks for your donation. Really, I have problems trying to tell the difference and I think I'm 1 for 20. I wish I could deduct the donation off my taxes.
🤑🥵😮💨
USN & USAF retired 1971-1993
Successful Transactions with more than 100 Members
All toning is artificial/environmental damage. RGDS!
What they call toning now - Tarnish is Tarnish IMo. It is external surface damage to the coin whether environmental or artificial. I stay away from tarnished coins what they call nowadays nt or at lol. If somebody wants pay more for what they think is nt it’s their money. But at my table…..just not a big fan of tarnish.
Overtime as tarnish oxidizes with the atmosphere it will get darker. Truly original is what the coin looked like GEM BU off the mint press.
Just start an llc and you can.
Paper money eventually returns to its intrinsic value. Zero. Voltaire. Ebay coinbowlllc
If you want to become an expert on toning, you will also want to gain an understanding of what caused the toning. Different coins and different series have very different attributes when it comes to toning. For example, the vast majority of toned Morgan dollars toned as a result of exposure to sulfur and other chemicals in the mint bags. Although there is a very wide range of types and colors of mint bag toning on Morgans, I think you could classify them into a half a dozen key categories. The various classic commemoratives often have distinctive toning related to methods of manufacture and distribution. For example, the toning will vary whether it is a Columbian or a Columbia or a Vancouver or an Antietam, but each of these has describable “typical” toning. Mint set toning on sets sold from 1947-1958 is usually distinctive, and I think people who have looked through many of them could describe different attributes by year. Then there is album toning or end roll toning or toning imparted by various tissue papers. It’s a fascinating topic and it is relevant to identifying AT versus NT. The doctors of course may try to imitate these historical toning processes, and some are very adept at it, but you are still in a better position if you know what to expect, for example on a 1926 Oregon Trail or a 1958 Franklin.