My second lesson with coins was to leave them alone.....

Older collectors, you've probably been through this before and thought it would be good to journal this for younger collectors.

It's easy to understand that having a great number of one type of coin could tempt a person to start cleaning to find those great pieces to show off from the collection. "Wow! It would be great if they didn't have the brown stains on them."

Several coins dealers in the area and books recommended dish soap followed by thourough drying with a non-scrtach cloth or rubbing the coin with a bit of oil from your forehead. Yeah, I even dipped a coin in thiosulfate to see what it would do.

After my experimentation, the detail on the coin turned out not so good (i.e., the removed dirt didn't uncover anything new), the dipping ruined the mint luster, or the forehead grease only shined the raised surfaces of the coin. The one dipped coin had reactions within the metal imperfections that permanently spotted the coin, visible by <10x magnification. Compared to a couple of good unaltered coins, my experiments looked terrible. There was a bit of anguish too because the coins were a gift.

There was also a storage issue with the dipped coin. Notice the iregularities in the airtite seal shown in the previous post. The air in a similary sealed coin continued to get into the air tite and corrode the dipped surface afterwards. The dip opened up the surface of the coin to increase the rate of corrosion with what little oxygen was getting in. Now I have a dark spotted, brown coin that is continuing to darken with a lot lower value and no chance of being graded.

Yes, there is a market for cleaned coins. Now, I'd prefer to go to NCS if the coin's value is worth it. Otherwise, leaving the coin alone is perfectly acceptable and less costly solution to having a hoard of great coins.

morgan-188