Coin cleaning

[cintitomcat]

I bought a rock tumbler from Harbor Freights, cleans coins but dont get the shine back. Coins have a dark tint. I put aquarium gravel half way, put in coins, add water until it's just over the coins then add dish soap. The gravel is a brownish color. I see pics of guys cleaned coins and they look good. Am i doing something wrong? Thanks

 

[Larry (IL)]

Are you tumbling the pennies separately?

I do the cents in a separate process with white vinegar in a quart jar and just shake the jar every now and then, you can also tumble them separately. About a half hour the cents are done while the silver colored clad takes 12 hours in the tumbler to look very nice. After drying on an old towel I spray a light coat of WD-40 on them and stir them up so all coins are coated and pops a shine and also helps the coins go through the banks coin counter without a problem. This picture is right before the WD-40.

I do have a few coins that are still dark and need to be tumbled longer to look good but the bank does not say anything about the few dark ones as long as most of them look good with no dirt on them.

 

[vlad]

Soak and stir/hand tumble for around 5 minutes to restore shine. If left too long or a dirty solution, the coins just get flat gray.

 

[cintitomcat]

I do tumble pennies separate, i change solution once but still dirty when i take coins out the second time. If they get that flat gray look can they be retumbled to shine up THanks