Cleaning Coin Finds -- An Incomplete Overview (long)

[geof_junk]

What I do now (not at the start) is check it against my best date/mintage of my collection after a quick blast under a tap and then put in an ultrasonic cleaning device (this removes most abrasive particles).  If the newly found coin is better then it gets a pampered dip in the warm spar-bath (bowl of warm water and a touch of detergent) and a gentle massage with my caressing fingers😊. If my coin in my collection is better then I don't care much what method I use. The transparent soft pencil eraser does a good job, I have even punished copper coin with a fine brass wire brush both methods make them prettier to most people but not collectors.  

[Rick N. MI]

Baking soda is an abrasive and will leave fine scratches. I've soaked of mine Hydrogen Peroxide.

I think now best would be to clean them dry with toothpicks and maybe a toothbrush. And even then it will probably leave some fine marks on a coin. So rare coin never clean.

[kac]

Taking the dirt off a coin that has been sitting in the dirt for 100+ years and possibly run over by tractors I would think would hardly hurt it's value. The real question I think is how much cleaning should be done. I try to leave the patina on them and not alter colors with chemical baths or solutions that have high acidic or base as that may react with the metal. Many coins I find have pine pitch on them and require something that can wash that off like acetone or naphtha.

How does hydrogen peroxide react with different metals?

 

[LipCa]

Fortunately, the only coins of any value I've found were a half a dozen gold coins and they cleaned up just fine under a stream of water in the kitchen sink(no brushing).   As all but one are EF or AU, any future cleaning will not be done by me.

As a side note, I found a really nice 1898 Indian Head penny once.   In the field it looked like it was not worn at all.

I cleaned it up in the kitchen sink with a soft brush and dish soap.  When done, I could not even read the date any more!!  The dish soap had taken all the surface off!   Who would have thought that would happen?   Never again......

[Rick N. MI]

I've only soaked copper in peroxide. It bubbles and takes the dirt off.

[GB_Amateur]

On 1/3/2020 at 4:33 PM, Steve Herschbach said:

Here are those prior cleaning and selling threads. I love my tag system!

I always try to tag original (thread starting) posts but when I looked (alphabetically, apparently) I didn't find this one.  When you write your "everything you ever wanted to know about using the detectorprospector.com forum" guide, 😁 could you please include the best way to access tagged topics?  I don't see an option in the search function, although maybe I overlooked that, too.

 

[kac]

Talked to my uncle and he said for general gold and silver use 8:1 water and amonia with couple drops of dish liquid. I just tested it on some clad along with a soft bristle toothbrush and it worked good even on copper and worked very well on a patina IH penny without removing the patina.

He said Phosphoric Acid may work well and that can be easily found in navel jelly rust remover. I thought I had some in my shop of horrors but can't find it.

Lastly testing an citrus based paint stripper on some coins that I dug at the beach which are in rough shape. Don't worry just clad.

[Joe D.]

Bleach, and ammonia!   And acids, and alkali's!  Etc.. can have very strong explosive reactions and/or make toxic gases!  Be aware, and have some knowledge of, what  your combining together!!  It sorta is, rocket science!  If your not sure, its safer to do experiments outdoors! And wear neoprene gloves and face protection!💥☠   🥽🧤

That's my public service announcement for today!     

 Take care all! 😊👍

[kac]

Update the paint stripper did nothing other than make the clad smell like a bag of oranges.

I also gave Trisodium Phosphate (TSP) used for cleaning walls etc prior to painting and it didn't do much at all.

So far the ammonia water and dish detergent does the best. Has a pretty low odor and think I'll make a batch of it for my ultrasonic cleaner.

Naval Jelly might be good on heavily corroded coins.

[Joe D.]

I think its great to try different formulas for cleaning coins, relics,  and EO,s (encrusted objects). I'm sure most of us are just trying to identify and preserve our finds! And are not concerned with grading, or creating museum pieces! 

  That being said, those pieces are out there, and are found! And if there is any doubt! Do nothing but protect in a static environment, until they can be seen by someone more knowledgeable!👍👍