Is there any truth to this??

[Vitruvius]

While researching ancient coins, I came across this on a website:

What Ancient Coin Dealers Won't Tell You!

Yes, there are a lot to collecting ancient coins, and many of the basic things that you should know are never spoken about! Not by dealers, because they want to get RID of lesser grade coins, etc. And not by collectors, simply because they just do not realize some of the differences! For example, dealers won't tell you whether the coins you buy were found by a metal detector in the soil or in large caches buried or hidden in pots or jars. This, believe it or not, makes a lot of difference in the value of a coin in many cases. For one thing, a coin that has lain in the ground for centuries, no matter what surrounding conditions are, is going to take on some of the minerals in the soil. It starts to 'crystalize'! It turns from 'metal' to a very brittle piece of mineralized/fossilized coin/metal. It may still LOOK like a coin, but it is no longer solid metal!!! If you were to try to bend one of these coins, it would not. It would break like a dry cracker! And, THAT, is what they will not tell you!!! You do not want to buy those kind of coins if at all possible, if you ever do, you do not want to think that it will have much chance of increasing in value. There are many of these coins around and no one knows a thing about this. But I am telling you about it here!

Is there any truth to this??  I'm just wondering..it seems like a stretch and I haven't seen anything about it at the Forum.

Thank you for any input!!

[Joe Sermarini]

Some ancient coins are brittle.  That is not a secret.  It is just a fact.   

I read that article years ago and if I remember right, it said good dealers don't have brittle coins while bad dealers do and they lie about it.  That is really nonsense.  Even the most expensive dealer will carry a crystalized dekadrachm.  It could still be a $100,000 coin.  But they won't lie about it.  Often you can't tell a coin is brittle just by looking at it.   In any case there aren't good dealers without brittle coins and bad liar dealers with crystalized coins.

Most brittle coins are frosty and rough.  They are also usually cheaper.  They are not really cheaper because they are brittle and might break.  They are cheaper because they aren't as pretty as a coin with nicer metal.  Even most frosty or even crystalized coins aren't as delicate as the article indicates.   Again, however, a coin can look fine and be brittle. 

Overall, I would say the article is highly inaccurate.  One thing to take from it:  Don't drop your ancient coins on ceramic or marble floors. 

[Vitruvius]

Thank you for the responses, gentlemen.  I thought this article was a little far-fetched.  I certainly can understand how an environment would affect a coin.  Just for fun, I took several uncleans that I had bought and tried to break them with my hands.  No such luck!  Even with a small aes that was paper thin, I couldn't snap it in half.  I figured I'd put this theory to the test.  These were all common uncleans, from 1.00 each to 5.00 each.  Not one broke    It just goes to show, you can't believe everything you read.  I do agree that you get what you paid for.  Speaking of which, I just purchased my first lot of uncleans from Forum!

Thanks once again, guys for sharing your knowledge

Tim

[peterpil19]

I read that article too a while ago, it sounded like it was written by somebody suffering from intense paranoia, or perhaps someone who had just spent a great deal of money on uncleaneds and found that they were all slugs!

--Peter

[Joe Sermarini]

The problem really only applies to silver coins.

[Robert_Brenchley]

In the main, yes, but I have a Carausius which has a recent chip, revealing that little or nothing of the metal remains, and the coin is now wholly or mostly oxides! I suspect there's a metal core in there somewhere or the thing would surely disintegrate.

[Pep]

I'm not exactly sure of the number but by looking at my collection and slug jars I've probably cleaned around five hundred coins by now.  Only one coin so far crumbled when I went to clean it.  It was a small AE4 with a two Victories facing reverse.  There was nice detail on it too   I think the ratio is still pretty low and nothing to be alarmed about, just be careful with the coins like others have said.

Kevin 

[bruce61813]

The problem really only applies to silver coins.

There is a yes and no answer to this. The crumbly coins, are rare, I , like Pep have seen only 2 or three out of 2000 uncleaned coins. They appear to be the just a minerilzed shell of the original coin, like a cast, the bronze reduced to copperoxide over the centuries. The case with the brittleness or crystalization in silver maybe an entirely diffent problem, although the symptoms my be the same. One possivbility may be what is called "work hardening". Just banging coins together caused the surface molecular structure to change. Gold, evey 18 karat can become hard and brittle just by repaeated tapping, this happens to rings all the time, and they must be annealed before thay can be worked, or they may break instaed of bend.
So small silver coins banging around over time can become brittle, and this may be truer of the thin coins. For the real answer you would need to consult a metualurgest on metal fatigue, but this is well known to most jewelers.

Bruce