Things You'll Need
Instructions
Place a sheet of aluminum foil onto the bottom of a glass container. Smooth out any wrinkles.
Boil water on the stove top or in the microwave and add it to the glass container.
Put the coin into the container so that it's sitting on top of the aluminum foil and completely submerged.
Measure out 3 tbsp. of washing soda and put it into the container. Stir to dissolve the washing soda.
Allow the coin to soak in the solution until the water becomes room temperature.
Dump the water and examine the coin. The burnt residue should be removed or diminished. If you can still see residue, use new tin foil, water and washing soda to repeat the process.