Does MS70 harm coins?

I am having an argument with someone online who disagrees with me that the coin cleaner MS70 does not take metal off of coins. Their opinion is that all coin cleaners remove metal from the coin. Does MS70 take any metal off of coins like E Zest? To my knowledge it doesn't have anything acidic in it. The only coins I don't use it on are coins made of copper or are corroded. The only problem I have had with MS70 is it may cause a coin to tone which I think may be from the coin having been previously dipped.

 

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They're confused.

Acidic coin dips, designed to remove tarnish from silver, can remove metal. So can other acids.

Strong alkalis, including MS70, can remove aluminum, zinc, and certain other active metals, but I can't see how they would remove copper/silver/gold.

I would consider rinsing/soaking a coin in distilled water, acetone, or xylene to be "cleaning" as well, and those certainly don't remove metal.

 

Here is MS70 MSDS, it would probably also work well as a drain cleaner.

http://www.translinesupply.com/PDF/MDSSHEETS/MS707530.MSDS.pdf

 

It helps remove stickers from plastic slabs too.

 

Yep, don't use it on an aluminum coin! It's the opposite of acidic, being on the alkaline end of the pH scale. So, depending on how you define 'cleaning' a coin, (ANYTHING including water, an acid dip, an alkaline bath, a good scrubbing, etc.). Saying 'all coin cleaners remove metal' is too broad a statement.

 

The dreaded C-word! Its sad to see so many coins ruined because people clean them; granted there may be some safe(er) cleaners/methods out there...but still, very frustrating to have a coin graded only to come back "cleaned", even when there is no visible sign that it had been cleaned. Somehow they can tell. One Morgan I bought came back cleaned and I gave the guy I bought it from all kinds of grief - he forked back over half the purchase price. Made for a nice hole-filler in the end!

 

Thanks for your input!

 

Depends which coins you clean and what you use. MS70 or other cleaners safe to use on rare coins may be great for uncirculated coins but you don't want to use it on a circulated coin because it will expose all of the scratches on the coin and collectors would prefer the dirt and original patina is left on the coin. The only reason you would want to clean a circulated or uncirculated coin would be to remove pvc or anything else that is harmful to a coin. But I would agree with you that original, uncleaned is best unless there is something on the coin that is harmful to the coin that needs to be removed.

 

Until I know for sure, I'm still in the camp that believes MS70 removes metal by removing whatever form of oxidized metal is on a coin's surface.

 

I don't know how these products work, and if some are safe or not.
But if something removes "toning", aren't atoms of oxidized metal being
stripped away?

 

This is a bit of a matter of definition. If by "metal" you only mean actual metal, that's one thing, but if by "metal" you also include salts of the metal, which are actually minerals, that's another thing. To my mind, "metal" refers only to actual metal, not mineral salts.

Alkalai does not dissolve gold, silver or copper, but it does dissolve salts of copper and silver that result from exposure to aqueous acids.

 

No if quick in the dip and out few seconds.

 

We're getting into terminology here, but I'd say that it's the oxidation process itself that's already removed the metal from the coin's surface. It's still sitting on the surface, but it's no longer acting as a part of the metal surface, particularly when it comes to optical effects.

Saying MS70 hurts a coin by removing metal is a bit like saying that a fall breeze harms a tree by stripping its leaves away. No, those leaves were already dead. (Now, if only a coin could regrow its original lustrous surface in the spring...)

 

Call me crazy but I think this guy is an idiot. He is now telling me that a coin treated with MS70 looks no different than a coin treated with E Zest. I am wondering if the guy is an official sponsor of E Zest and he is purposely giving me misleading information. I've treated many coins with MS70 an I never get the washed-out look you would get from treating a coin with E Zest. He says he is a dealer with 20 years experience.

 

E-Z-EST contains sulfuric acid and thiourea, and MS-70 doesn't have acid.
They are not the same. Not all coin dealers are experts.
On the MS 70 it says: Contains caustic soda.
What does that mean, lye?

Here is an old link about some of this stuff:
https://www.cointalk.com/threads/have-you-tried-the-chemical-ms-70.285346/

 

Yes caustic soda ( because it corrodes mineral salts) , Sodium Hydroxide, Lye, and NaOH are the same, but possible differing in concentration/naming in compounds.

 

Details that aren't important:

Caustic stems from the ability to attack organic tissue, not metals or salts, although there are plenty of caustic substances that will do both.

MS70 contains potassium hydroxide, not sodium hydroxide. Potassium hydroxide probably dissolves better in the solvent MS70 uses, but its effects on skin and metal are the same as sodium hydroxide. Don't get it on your skin; if you do, flush it away with lots of water, or you'll be sore.

Detail that is important: this "dealer with 20 years experience" either (a) doesn't know what he's talking about, (b) is trying to mislead you, or (c) both.

 

Some photos from my old Numismatic Scrapbook periodical in 1963






Sounds similar , Hopefully all will note the misleading ,Jim

 

Picking a few nits...caustic soda is sodium hydroxide, but MS70 contains Potassium Hydroxide, caustic potash.