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How to Rainbow Tone Coins

Coin toning is quite simply the process of tarnishing a coin. Collectors will use a coin's tone in order to establish its value. A naturally well-toned coin may be more valuable than a clean one, depending on the coin. You can also artificially tone coins using a variety of chemical processes. The various coins will require different chemicals in order to turn different colors.

Things You'll Need

Protective gloves
Safety goggles
Potassium sulfide
Water
Small plastic mixing bowl
Tongs

Instructions

- 1
  Mix 20 milliliters of potassium sulfide with 80 milliliters of water in a small plastic mixing bowl. After the potassium sulfide has dissolved in the water, it will create hydrogen sulfide.
- 2
  Dip the coin into the hydrogen sulfide using tongs. Leave it there for five minutes or so, and then remove it.
- 3
  Allow the coin some time to dry and for the rainbow toning to formulate. Then repeat the process until the coin is rainbow toned.

Rocks & Minerals