Hello, this is a brand new and easy method with silver coin and electroplating in silver nitrate and lye with some zinc. It plates a beautiful black to grey silver onto copper and maybe brass. It can even be done passively but I recommend not going past 9 volts.
Going past 9 volts 1 Amp of current may cause the silver to flake off. Remember this current and voltage has to be no more than 9 W of power. If it 10-20 percent lower than this it will work better.
Warning: Lye is corrosive and toxic. Silver nitrate is toxic and stains skin badly, and zinc sulfate is highly irritating. Please wear PPE (Gloves and safety goggles when using these chemicals).
25 to 50 g of Silver Nitrate 98 percent.
90 to 95 percent Lye (Sodium hydroxide, or Potassium hydroxide).
98 percent of zinc sulfate salt.
Copper or copper pipes.
Wires with alligator clips.
9 volt, 500 mA to 1 Amp DC power supply (Phone jack, etc),
Optional a Power supply (worth 100 dollars).
Thin wires copper type 1 mm thick (check Amazon for this)....
Scale 100 g times +- 0.1 g to 500 g.
Potassium nitrate or Magnesium Nitrate.
Tween 20 or Dish Detergent.
Urethane paint preferred clear but white will do (Not black or grey).
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Step 1: Setting Up Coin and Silver Bath.
In order for this to work you need a 0.5 ounce Silver coin for positive and for negative is the copper pipe.
Optional could between 20 or dish detergent. Please see video for more info on how to silver plate. It very similar except you add lye 10 g and 5 g of Zinc sulfate.
Here for silver plating here some more for dark black plating (Silver oxide).
Step 2: Hooking Up the Wires to the Device ( Clamps Are Essential).
Letting the power supply or the voltage at 9 volts 1 amp or so run through the solution. Add 1 g of silver nitrate to 10 g of Sodium or Potassium hydroxide, and 5 g of zinc sulfate to 2 L of tap water. Normally silver requires distilled pure water due to chlorine reacting with silver but this is not the case for the prep of black grey silver method.
Using a clamp make the positive rale of voltage wire attach to the clamp so only 3/4 of the silver coin is in the solution and make sure the clip does not enter the solution use the clamp to prevent this. If not corrosion of the wire and contamination can occur.
The negative rail should be attached to the wire I described in step 1.
Step 3: Proper Chemical Prep for Direct Silver Plating.
Please see the videos on Silver plating that I provided but for 750 ml of water (Distilled then about 5 g of Magnesium Nitrate (Prop will work) with Silver nitrate and Tween 20 (0.1 g) or a few drops of dish detergent can be done.
It has been done and I don't have any pics on it except for one. It works better with ultra clean electrodes.
Attach the electrodes - and + as shown in the videos with Paul the Inventor.
Again using distilled water and a power supply with wires (watch the polarity!).
Step 4: Coating With Urethane.
After coating threw electroplating wash and dry with acetone and paper towels. A low lint type is preferred. Using a Big Jar put Open up the can and place spoonwise sample over the wire that has been hanging over the glass lid. Do this until all have been soaked twice.
I find this an easier method than before just pouring it into a clean jar with the wire it min the contamination into the Urethane lacquer.
It has a unique color the reason why I got a lighter coat was due to too little Zinc sulfate and or Silver nitrate or adding too much lye.