When Is It Acceptable To Dip?

Here is my Two Cents on cleaning: first, when you own a coin, you can do whatever you want with it. Dip it, polish it, drill holes in it, whatever. However, many of those things will reduce the resale value. The first thing I try is acetone. I dip a q-tip (paper stick,not plastic) in acetone and wipe the coin with it. Acetone will remove surface debris without reacting with the metal (high grade copper excepted) and evaporates completely without rinsing. Next, I will try MS70 on lustrous nickel and silver coins. MS70 Will give circulated and gold coins a washed out look. MS70 is a surfactant (soap) and if properly rinsed will not leave any residue. It will even remove light toning. Last I might try E-Z-Est far tarnished Wil Dr coins. The active ingredient is thiuric acid. The problem with it is if it is not completely neutralized with baking soda the coins are likely to refine over time in a very ugly way. If you try it on nickel you might get an immediately pleasing result but over time the nickel will turn an ugly brown. If you try MS70 after dipping it can be like painting the coin brown. Let's face it, many coins need help to have eye appeal. Trying these things can help, but nothing is guaranteed. Get some experience on coins that do not matter and then you will know what to try on coins that do.

Wait .....wait .....wait...... the pictures are fuzzy and my sight is not what it used to be, but are we looking at a 1928 here ?

I read every post, and no one has mentioned that dipping should only be done to an uncirculated coin. I'm not sure if the one you showed is uncirculated, but the way you described it in the beginning as a 20 dollar bin coin, it didn't sound like it. So, in your case, no, I would not dip it.

Great replies so far thanks guys. And no it's a 1923 but it does look like a 28 from the picture. I wish it was!

I don't routinely dip coins but have done so many, many times. Diluted dips are worth a try on some ugly coins but only if you know what you're doing. A large number of 19th century U.S. silver and gold coins have been dipped. Some people say most coins have been dipped but there's no way to know. There is a cottage industry in toning and re-toning for profit and many of these "doctors" dip before operating. :(

Dipping in thoracic acid was a common and accepted practice on AU and MS coins for many decades. Recent decades have brought about a greater appreciation for originality so many haven't been re-dipped, and some have re-toned, over the past 50, 60 or 70 years. That's a good thing.

If you must dip then use common-date bullion coins and dilute your dip with 50% distilled water and rinse the coin throughly when complete.

I take the view that I do not really own the coins, I am merely their custodian and curator. Some day I will be gone but the coins will remain and it is my responsibility to try and preserve them for future custodians as undamaged as possible.

......... we are merely the caretakers of a small part of history. Dipping a coin strips off a layer of metal at a molecular level. To me, that is stripping off a layer of history. When I look ay my classic coins, every nick, every scratch, bag mark, fingerprint tells a story of where and with whom the coin has been.

But that is just me.