How are sunken coins cleaned and handled?

How are sunken treasure silver coin hordes from buried or sunken treasures handled before they are put on display in a museum or turned over to the collector market? Do they just put them on display as-is or turn them over to the collector market as-is, complete with encrusted dirt, grime and barnacles? Or do they have them cleaned and restored? If so, who cleans these coins in such an instance? What is the procedure they use? If they do clean them, doesn't this go against the numismatists sacred oath to NEVER clean them? Don't some of these discovered silver (or even gold for that matter) coin hoardes get sold or auctioned off to the collector market? Do the auction houses have them professionally cleaned before selling them? I thought this was a big no-no. I thought you are supposed to leave the crud and barnacles on them for autheticity's sake. Who's to say the coins were cleaned properly and professionally? Doesn't this remove the historic value of the coin? Doesn't this subrtract from the authiticity of the coins? Maybe they botched the cleaning job, but the coins are so rare and desirable that collectors look the other way and buy them anyway. I was just wondering how this is usually handled. Anyone know?

 

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Hope that helps.
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As for specific ways they clean the coins, I'm not sure. I'm not big into the whole sunken treasures side of things, nor the cleaning aspect.

 

There is a distinction between coin cleaning and coin conservation. There are numerous threads here that discuss both.

 

I recently bought a Spanish 8 Reale that was described as a shipwreck coin. When I got it , it had not only been cleaned, but it was polished as well. Fortunately the seller gave me a full refund, including postage for sending it back.

 

How are they cleaned?
Generally:
Poorly.

 

I do remember seeing something about soaking the silver coins in some kind of solution to remove all traces of salt to prevent the crumbling that GD mentioned. I wish I could remember more details if it included electrolesis or just a soak. I do recall it is a very long process.

 

I found a good site that goes throuh the process. click here

 

I'm not sure but I've seen old coins in museums that were supposed to have been found in the ground, in the water, on sunken ships, etc. All looked like someone had cleaned them completely and keep them cleaned. I would suspect that such places are not in the buisness of selling coins so they don't really care about cleaning them. They are for display purposes for the general public and not just for coin collectors. The average person wants to see pretty coins, not ugly, corroded, tarnised, toned, dirty things. So cleaning old coins from such places may just be that, cleaned.

 

Museums and Archaeologist aren't the best Coin custodians, to say the least...

 

The "big" treasure hunting company is located here in Tampa. As far as I know NGC has always handled all their coin restoration and many get slabbed with the shipwreck included on the slab. Others are in a slick presentation frame with some history about the ship and the coin. Usually one dealer broker all the coins sold to the public. I have a DVD that shows a lot this in detail. The problem with shipwreck coins is they have a hudge initial price, but the price falls after all the hoopla. If I understand correctly NGC has someone on the ship when the coins are hoisted up out of the water and Doug is correct they are kept in salt water until the process begins. According to the DVD NGC has a "secret" location where all the coins are taken for restoration. A few people around here invest with this company, and it appears they have done well. I will say it is amazing the before and after pictures of these recovered coins.

 

Yes, it's like a big, "Don't try this at home" disclaimer.

 

This thread reminds me of the new show on the discovery channel called Treasure Quest. I think the show is interesting and shows how carefull they (Odyssey Marine) are, at least with the initial discovery, and shows some of the obstacles they have to fave when claiming a treasure.

One episode showed 5 gallon pails lined up in the airplane seats getting a ride back to the states. They were all full of coins they had recovered. Almost enough to make you drool.

Another showed them diving for submarines sank in WWII trying to ID them for relatives and country of the men aboard when the boats sank.

 

I love that show. The TiVo is set to record it every week.

 

i found a lot of coins in the ocean around cape cod Massachusetts but they all are encrusted with ocean water. a lot of them have this green (in color) substance on them some one said that it could be gold coins I cant make out any names or dates on them im looking for someone that knows about these coins and about how much they are worth the other coins that I have all have a blackish substance on them in all I have about 60 coins and there are more in the ocean where I found these ones (which ill be glad to go get if they are worth something ) Edited: Buy/sell/trade discussion can only be in the advertising subforums, and email addresses create spam and webbots, so use 'conversation' PM messages among members.

 

Yes, I clean coins, but...
if I pay them to do it, they conserve it

 

Pictures are worth a thousand words

 

I would call NGC and see if they'll conserve a few to see if you have any gold or silver but my suggestion is to get your butt back out there and get all you can find ASAP!!! And keep them in buckets of saltwater (from ocean to directly to bucket as fast as you can) until you know what to do with them

 

I've seen the coins that came into NCS. I've never seen a gold coin there or anywhere with green incrustation. Normally, it is brownish. However, I guess anything can happen in nature.

If you cannot see ANY type of detail, they are probably too corroded to be worth much UNLESS...

You have two routes. Grab all you can get (hard to believe you left anything behind) and forget about the marine archeology aspect OR notify a museum and let them "map" the find, discover where the coins came from and the ship. Then, you'll come out with less money but even the corroded junk will be worth something and you'll have fifteen minutes of fame in your geological region.

Put some photo's up of your treasure.