# Numismatists: are old coins more valuable with/without patina? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [March 10, 2017, 2:07pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863 "2017-03-10T14:07:35Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [March 10, 2017, 2:07pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/1 "2017-03-10T14:07:35Z")
I have some Japanese coins dating back over approximately 100 years. Some of them are very well weathered/tarnished. I am considering selling them, and wondering whether I should clean/polish them before putting them up for sale. Will they be considered more valuable with their patina intact, or with the shiny look of a brand-new coin? ---
**Author:** ![CoastalMaineiac](https://avatars.discourse-cdn.com/v4/letter/c/e8c25b/32.png) [@CoastalMaineiac](https://boards.straightdope.com/u/CoastalMaineiac)\ **Post date:** [March 10, 2017, 2:10pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/2 "2017-03-10T14:10:06Z")
> [@Machine\_Elf](#): > > I have some Japanese coins dating back over approximately 100 years. Some of them are very well weathered/tarnished. I am considering selling them, and wondering whether I should clean/polish them before putting them up for sale. > > Will they be considered more valuable with their patina intact, or with the shiny look of a brand-new coin? > **[Should You Clean Coins Or Not? (Hint: NO!)](https://coins.thefuntimesguide.com/cleaning_coins/)** > > If a coin is bright and shiny because it was well preserved or just came from the Mint, that is a good thing. However, if a coin is bright and shiny because it was cleaned by an amateur, that is a whole different story. Cleaning a coin generally... ---
**Author:** ![Telemark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/telemark/32/372_2.png) [@Telemark](https://boards.straightdope.com/u/Telemark)\ **Post date:** [March 10, 2017, 2:13pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/3 "2017-03-10T14:13:29Z")
The general rule is that you shouldn’t clean old coins. Most non-professionals will due it wrong, damaging the coin and reducing its value. And there’s no point in cleaning off the patina - it is part of the coin. Old coins are valuable because they are old, not because they are shiny. [This article](https://coins.thefuntimesguide.com/how-to-clean-coins/) recommends only using water and a soft cloth if you must touch them up. ---
**Author:** ![samclem](https://avatars.discourse-cdn.com/v4/letter/s/a9a28c/32.png) [@samclem](https://boards.straightdope.com/u/samclem)\ **Post date:** [March 10, 2017, 2:23pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/4 "2017-03-10T14:23:10Z")
Don’t clean them–period/full stop. This from a professional numismatist. ---
**Author:** ![kopek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kopek/32/337_2.png) [@kopek](https://boards.straightdope.com/u/kopek)\ **Post date:** [March 10, 2017, 2:56pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/5 "2017-03-10T14:56:18Z")
> [@samclem](#): > > Don’t clean them–period/full stop. This from a professional numismatist. Retired but seconded. ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [March 10, 2017, 3:02pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/6 "2017-03-10T15:02:48Z")
Don’t you watch Pawn Stars or any other show like that? Never clean coins or anything else old!!! ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [March 10, 2017, 4:08pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/7 "2017-03-10T16:08:23Z")
You have to realize that patina, or toning, isn’t something that’s been added to the surface, like grime. It IS the surface, and to remove it is to remove the actual surface of the coin. Do you really think that what’s remaining will have the original luster of a new coin? Don’t do it. Oh, and many collectors specifically seek out coins that have interesting patina, especially what’s known as “rainbow” toning. ---
**Author:** ![Kimballkid](https://avatars.discourse-cdn.com/v4/letter/k/b5a626/32.png) [@Kimballkid](https://boards.straightdope.com/u/Kimballkid)\ **Post date:** [March 10, 2017, 4:26pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/8 "2017-03-10T16:26:17Z")
[These](http://www.jhonecash.com/coins/tonedmorgans.asp) (scroll down) are some extreme examples, but toning on coins can be really quite striking and beautiful and add to the overall desirability. ---
**Author:** ![mixdenny](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mixdenny/32/2962_2.png) [@mixdenny](https://boards.straightdope.com/u/mixdenny)\ **Post date:** [March 10, 2017, 5:34pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/9 "2017-03-10T17:34:41Z")
I talked to a numismatist about this once. My point was that given a coin had been rattling around in pockets with other change for decades, that you could still see if it had been gently cleaned with a soft cloth? He simply replied, “Absolutely.” Dennis T ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [March 10, 2017, 5:43pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/10 "2017-03-10T17:43:50Z")
> [@panache45](#): > > You have to realize that patina, or toning, isn’t something that’s been added to the surface, like grime. It IS the surface, and to remove it is to remove the actual surface of the coin. Do you really think that what’s remaining will have the original luster of a new coin? Don’t do it. I’m not any sort of numismatist, so no, I don’t know these things at all. My only experience in this area involves childhood experiments in [cleaning pennies with vinegar,](https://sciencebob.com/clean-pennies-with-vinegar/) which I recall left pretty shiny-looking copper. Anyway, message received, thanks to all who contributed; I will refrain from cleaning any of these coins before sale. ---
**Author:** ![mcgato](https://avatars.discourse-cdn.com/v4/letter/m/ac8455/32.png) [@mcgato](https://boards.straightdope.com/u/mcgato)\ **Post date:** [March 10, 2017, 7:36pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/11 "2017-03-10T19:36:39Z")
[The tale of an 1850 double eagle](https://www.youtube.com/watch?v=mk0F_sQY-kM): a guy buys an 1850 gold $20 double eagle for $102,000. He cleaned and polished it to a mirror like finish. Turned something worth about $250,000 into something worth $10,000. ---
**Author:** ![Amateur\_Barbarian](https://avatars.discourse-cdn.com/v4/letter/a/59ef9b/32.png) [@Amateur\_Barbarian](https://boards.straightdope.com/u/Amateur_Barbarian)\ **Post date:** [March 10, 2017, 9:16pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/12 "2017-03-10T21:16:30Z")
> [@Kimballkid](#): > > [These](http://www.jhonecash.com/coins/tonedmorgans.asp) (scroll down) are some extreme examples, but toning on coins can be really quite striking and beautiful and add to the overall desirability. Those would be so pretty if someone just buffed the silver spots off. 😉 Seriously, those are some beautiful unicorns. ---
**Author:** ![kopek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kopek/32/337_2.png) [@kopek](https://boards.straightdope.com/u/kopek)\ **Post date:** [March 11, 2017, 3:25am UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/13 "2017-03-11T03:25:51Z")
> [@silenus](#): > > Don’t you watch Pawn Stars or any other show like that? Since you mentioned that show, I always felt they were a great bad example. They always say don’t and then they turn all this stuff over to that restoration guy who cleans and repaints it to the point I would never want it. OK – it isn’t coins; but the same holds true for a lot of the other things they have butchered for them too. ---
**Author:** ![RivkahChaya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rivkahchaya/32/8919_2.png) [@RivkahChaya](https://boards.straightdope.com/u/RivkahChaya)\ **Post date:** [March 11, 2017, 3:38am UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/14 "2017-03-11T03:38:19Z")
> [@samclem](#): > > Don’t clean them–period/full stop. This from a professional numismatist. Coin collector from the age of 10, and granddaughter of a journalist who had a syndicated column on money and coins in the 70s. Coins should be cleaned only it they have actual mud or something on them, and then very carefully with distilled water and a very soft cloth used to blot, not rub. It’s very tricky, because you want to get the grime off WITHOUT getting the tarnish/patina off, or scratching the coin. Sounds like what you have should under no circumstances be cleaned. ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [March 11, 2017, 1:16pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/15 "2017-03-11T13:16:35Z")
> [@mcgato](#): > > [The tale of an 1850 double eagle](https://www.youtube.com/watch?v=mk0F_sQY-kM): a guy buys an 1850 gold $20 double eagle for $102,000. He cleaned and polished it to a mirror like finish. Turned something worth about $250,000 into something worth $10,000. This reminds me of a story told long ago on a usenet coin group. A guy inherits a pile of Morgan dollars, arranges a meeting with a coin dealer (the dealer was the one telling the story.) Dealer finds out that a friend had told the guy to polish up the coins really well to make them as valuable as possible. Dealer tells guy that the coins are now worthless as collector’s items and are worth pretty much their melt value. Guy assumes that dealer is attempting to rip him off, storms off in a huff. Later on, the guy contacts the dealer again, to tell him that he wished he had believed what he was told. Turns out that after the meeting, the guy subscribed to one of the slabbing services, which charges an up front fee plus a per coin fee for grading them. With the number of coins he had, the fee for grading all the Morgans was in the high hundreds or low thousands (I don’t remember exactly.) Every coin came back labeled as “cleaned, ungradable.” ---
**Author:** ![Common\_Tater](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/common_tater/32/13846_2.png) [@Common\_Tater](https://boards.straightdope.com/u/Common_Tater)\ **Post date:** [March 11, 2017, 5:52pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/16 "2017-03-11T17:52:43Z")
It isn’t just collectable coins, many antiques or collectibles have had their value seriously diminished by well meaning folks who try to spiffy things up with a whiz-wheel or coat of paint, varnish etc. Toys and guitars for example. The rule is, “leave it alone”, if somebody is interested in buying your newfound Treasure, they’ll know what it is and what to do with it, what not to do with it. Olive oil has been used to clean ancient Roman coins, not really “cleaning” as in popular usage, actually soaking for long periods of time. Don’t know how that factors, I’d think that would be harmless enough. ---
**Author:** ![samclem](https://avatars.discourse-cdn.com/v4/letter/s/a9a28c/32.png) [@samclem](https://boards.straightdope.com/u/samclem)\ **Post date:** [March 11, 2017, 11:57pm UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/17 "2017-03-11T23:57:14Z")
> [@Common\_Tater](#): > > Olive oil has been used to clean ancient Roman coins, not really “cleaning” as in popular usage, actually soaking for long periods of time. Don’t know how that factors, I’d think that would be harmless enough. Harmless. Improves the coins perhaps 10-25%. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [March 12, 2017, 12:40am UTC](https://boards.straightdope.com/t/numismatists-are-old-coins-more-valuable-with-without-patina/781863/18 "2017-03-12T00:40:15Z")
> [@Common\_Tater](#): > > It isn’t just collectable coins, many antiques or collectibles have had their value seriously diminished by well meaning folks who try to spiffy things up with a whiz-wheel or coat of paint, varnish etc. Toys and guitars for example. And violins. Back when I was in middle school, I “improved” my fiddle with a coat of varnish. Had to get a new one.