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I use this method but with Calcium Carbonate in the water for theelectrolyte. It is recommended by salvage divers. They are trying toget the mineralization out of the object. It is what caused thecorrosion in the first place. The few things I have to add are asfollows:

1) Use Calcium Carbonate (Get cheaply at hot-tub/pool supply store)

2) Add in a ratio of 48:1 (water to calcium carbonate.)PH-11 is ideal

3) Adjust the current down to the point the fizzing slows down andthen bring it up high enough to do the job. Any higher will just takemetal away from the coin. Never go over 2 Amperes and try to stayunder 1 Ampere (for small objects such as coins.)

4) Use a constant current power supply with current limit or circuitbreaker/fuse protection on the DC secondary if available. 6-12 VDCwill be fine for the electrolyte, 15-25 VDC may be necessary for therinse. NEVER USE OVER 30 VDC! There will be a SHOCK HAZARD! Always usea transformer-isolated type power supply!

5) Use something to fix the distance RELIABLY between the Anode(+)&Cathode(-)or Coin to be cleaned. If they get closer the current willrise and your coin will lose metal! If they touch, the power supplywill short which may damage the equipment or cause a fire.

4) Use distilled water or you may add minerals and impurities thatruin your coin. It's cheap! Or get some from your de-humidifier orrainwater is pretty good (unless you are in a very polluted area!)

5) Never leave a good coin alone with this method. You will be sorrysooner or later! Check it often! Practice first with cheap coins!

6) When done, you must rinse out the coin in clean distilled waterthen you MUST put new distilled water in a clean bowl and use a freshAnode (+) Electrode and do it again WITHOUT the Electrolyte (CalciumCarbonate.)This step is essential to remove all traces of theelectrolyte from the coin! You will have to turn the voltage up higheron your power supply just to get a little fizzing. This is normal asdistilled water is not a great conductor. After adjusted for slightfizzing, you can let it sit for 7-12 hours (under supervision checks.)

7) Use a stainless steel fork, spoon for the anode and change/cut-offa new piece every time you change the solution. Don't try to reuse it!

8) You can do more than one coin at a time but you MUST NOT use thesame solution with coins of different metals! Do not mix CLADS withCopper, silver or Nickel Nickel's!! If not sure do it separately!

9) Practice on your corroded Lincoln pennies, Rosey dimes, JeffersonNickels and Wash. Quarters that are not VALUABLE! Age them yourself ifyou must in a salt or chlorine solution.

10) Protect your eyes and skin as the solution is caustic.

11) Use good ventilation as this process does produce fumes.

12) Use #16 wire to connect the Anode and Cathode. Use Flat grip=20alligator clips or a plastic basket and wire wrap around the coin togrip it without leaving marks. Standard "sawtooth" alligator clips candamage the finish of your good coins. Try to put as little of thecopper wire, alligator clip or other different metal in the solutionas possible.

Email Bob Zito