.

Similarly, you may ask, can you clean coins without losing value?

First DO NOT clean valuable coins. Most collectors rarely clean a coin as it can greatly reduce its value. Distilled water is best as most water is now treated with fluoride and this can cause different chemical reaction with some coins as many coins have several metals within them when they are minted.

how do professionals clean old coins? Clean old coins with vinegar. Let the coin soak for a few minutes. Then grasp the coin by its edges, pull it out of the vinegar, and rinse it clean with distilled water. If the coin is still tarnished or dirty, try brushing it gently with a soft toothbrush. Be careful not to scratch the surface of the coin, however.

Then, why clean coins reduce value?

There's a reason that a cleaned coin is often worth less than half its original, undamaged value – numismatists simply don't want them. In fact, in most cases, anything more than a simple surface rinsing with water to dislocate loose debris will actually remove tiny bits of metal from the coin.

Should I clean coins before selling them?

It is best not to clean patina off rare coins as the value can be reduced. 99% of coins do not increase in value after you clean them. However, when some collectors try to sell out some coins because they are either get bored with them or want create space for the new coins, they think of cleaning the coins.