Βι¶ΉΤΌΕΔ

Ancient and ArchaeologyΒ  permalink

cleaning old coins

• Message 1.Β 

  Posted by hob-goblin (U3781859) on Tuesday, 18th April 2006

  Any tips on cleaning old coins? Found a 1911 half sovereign and it's 22ct gold, what's the best way to clean it?

  Link to this forum: cleaning old coins

  Report message1

• Message 2

  , in reply to message 1.

  Posted by an ex-nordmann - it has ceased to exist (U3472955) on Tuesday, 18th April 2006

  Why clean it? Any numismatist - or dealer in antique coins - will tell you not to do so. It takes from the coin's value rather than adds to it, and in my own opinion just makes a lovely coin look plain silly! :o)
  
  As it happens (and if you really must clean it) gold is one of the easiest metals to wash when it comes to coins. Warm soapy water should remove most soil and grit without discolouring the metal. But a word of warning - gold is also one of the easiest surfaces to damage abrasively, and grit is an abrasive, even when removed with the softest of cloths.

  Link to this forum: cleaning old coins

  Report message2

• Message 3

  , in reply to message 2.

  Posted by DL (U1683040) on Wednesday, 19th April 2006

  On gold you can use practically anything short of concentrated hydrochloric acid!! More seriously, I'd recommend just hot water and a mild soap. Alternatively you could use an ultrasonic cleaner, which simply causes the dirt to dissolve away.
  Gold doesn't tend to tarnish, so I'd be a bit concerned if it shows any kind of corrosion, since that would indicate that it ain't gold! As Nordmann says, avoid anything abrasive, stick to soaking or ultrasonics as a cleaning method.
  
  With respect to cleaning coins, it does depend entirely on the type of coin. If we're talking Roman ones which have 1800 years of mud stuck to them, there is usually no option about cleaning it, you have to simply to find out what the coin is, since a disc coated in concreted mud isn't work anything! If you're talking about bronze coins, then it is almost an art form. You have to clean them to some degree to show the detail, or the coin has no value, but you also need to keep the patina (the coating of oxidised metal that accrues over time on the coin) intact, since a coin where bare metal is showing is worth very little also. For bronzes, stick to soaking in olive oil (it sucks out the dirt, but leaves the coin intact, no idea how!), and brushing lightly with a very soft brass brush. It takes weeks, although ultrasonic machines do the job in an hour or so. For silver, just soap and water is enough, but try not to remove all the toning (the black ageing on it), this is what gives the coin its "antique" look, and again adds value. On all coins, patience is highly necessary, rush it and you can destroy the coin.
  
  Cheers
  

  Link to this forum: cleaning old coins

  Report message3

• Message 4

  , in reply to message 3.

  Posted by CorePersephone (U3724174) on Wednesday, 19th April 2006

  Do you collect coins? I do. If you want to get off like big hunks of dirt I would recommend using a brush or something but to get it to be all shiny and new I use luster on my coins.

  Link to this forum: cleaning old coins

  Report message4

• Message 5

  , in reply to message 4.

  Posted by DL (U1683040) on Thursday, 20th April 2006

  What sort of coins do you collect?
  
  I usually try to avoid any sort of polish, since you never can tell what effect it will have on the metal!
  

  Link to this forum: cleaning old coins

  Report message5

• Message 6

  , in reply to message 5.

  Posted by thegoodbadugly (U2942713) on Friday, 21st April 2006

  dipping bronze in olive oil is a good tip thank you dl

  Link to this forum: cleaning old coins

  Report message6

• Message 7

  , in reply to message 1.

  Posted by Plancenoit (U1237957) on Friday, 21st April 2006

  For anything post c.1200, remove all soil/dirt by soaking in distilled water for about 1 hour, then drop it in a tumbler of Tomato Sauce for about 30-40 mins (perhaps a little longer). Rinse, again in distilled water, and it will look as good as the day it was dropped/lost/buried. Don't use a cloth or an abrasive of any kind.
  
  Don't laugh, it works!! Try it on something worthless like a Victorian penny, or even a modern one.
  
  It takes away all the poop and leaves you with a coin that looks as it was. Some kind of chemical reaction that I couldn't even begin to explain.

  Link to this forum: cleaning old coins

  Report message7

• Message 8

  , in reply to message 5.

  Posted by CorePersephone (U3724174) on Friday, 21st April 2006

  I collect both American coins and coins from other countries. My favorites are my peace dollar, my coins from Hong Kong, and ones with animals on them :D I also collect paper money though I have much more coins. I don't collect commemorative coins, tokens, or things that can't be spent.

  Link to this forum: cleaning old coins

  Report message8

Back to top