Cleaning Coins

Science fair

Purpose Statement

The purpose of this experiment was to see which liquid cleans coins the best. I became interested in this experiment because we get a lot of dirty coins when we get change. The information gained from this experiment will help others learn more about clean coins and how to make them look rich


There are a lot of websites that say salt and vinigar would be the best to clean coins. Some say gasoline, so I will be the best so I will see which one would be the best.

Coins are made of copper and nickel so the best way to clean is with the salt. The vinegar will give a boost in the cleaning process and the efficiency.


My hypothesis is salt and vinegar together will clean coins the best. I base my hypothesis on the research I have searched.


3 toothbrushes



3 cups




  1. Get vinigar, salt, gasoline, coca-cola, 3 cups, 3 toothbrushes, flashlight, and coins.

  2. Put gasoline in one cup

  3. Put Salt and vinegar in another

  4. Put coca-cola in another

  5. Dip one coin in each cup

  6. Keep the coin in the solution for 30 sec.

  7. Brush them with toothbrush

  8. Do this 3 times

  9. Use a flashlight to see which coin has the strongest reflection.

10.Take pictures

IV: Liquid
DV: Cleanliness
CV: Coin each time use the same liquid as the first time


The original purpose of this experiment was to see which liquid would be the best to clean a coin and make it shine the most. The results of the experiment was the Coka-Cola was the best to clean the coin. The next would be Salt and Vinegar was better than gasoline.

Big image


My hypothesis was salt and vinegar will clean the coins the best. I base my hypothesis on the research I have searched. The results indicate that this hypothesis should be considered wrong.Based on the results of this experiment if you clean a coin use Coka-Cola. If I were to conduct this science fair project again I would maybe do more liquids and buy some coin cleaner from a store a compare it to Coka-Cola.


If you were ever to clean a coin you should use Coka-Cola.You should not use gasoline for two reasons. One it smells. Two it is not the best at cleaning coins.