If you collect coins, then this useful tip will be very useful for you. Over time, the surface of the coins loses its luster, oxidizes, and dims. But there is one simple way how to restore their former shine. And an ordinary copper coin will turn into a "gold".
For this we need 10g. zinc sulfate, zinc, copper coins and a measuring cup.
Mix 10g of zinc sulfate, 50 ml. hot water, zinc and coins in a small pan. Then, constantly stirring, boil for about 15 minutes. Zinc must be in contact with the coins.
Coins should be coated with a thin layer of zinc and become “silver”.
The next step is to heat the coin in a hot pan. And she, just before your eyes, turn into a "gold".
These are the wonders of chemistry!