What is the knowledge of coin collection?

Hello, my friend, I will tell you how to collect coins.

First, don't touch the coins with your hands. Newly issued coins or washed coins are easy to leave fingerprints or sweat marks when touched by hands, especially wet or sweaty hands. When appreciating coins, you can wear thin gloves or pick them up with soft plastic tweezers.

Second, coins should not be stored in humid or oxidizing gas environment. Most coins will rust in a humid environment, especially those made of copper and aluminum. The surface blackening of silver coins is caused by contact with harmful gases such as hydrogen sulfide. Therefore, coins should be kept in a dry place. Sealed circulating commemorative coin cards or sample coins, as well as gold and silver coins, it is best not to open envelopes or sealed boxes.

Third, coins should not touch acid and alkali. Coins will oxidize and change color when exposed to acid and alkali. Even the most inactive metallic gold will melt when it meets "aqua regia". After the oxidized and rusted coins are rusted with acid and alkali, they should be washed with clear water several times immediately, wiped clean with a soft cloth, and dried if possible.

Fourth, don't misplace coins. Don't misplace all kinds of coins and collide with each other. Excess coins or coins for exchange should be packed and stored in soft plastic bags. This can not only prevent coins from touching humid air, but also prevent them from touching with hands when watching or communicating with people.

In addition, collect coins in case of fire. When a coin meets fire, it will destroy the color and texture of the coin, and it will be seriously deformed, reducing or even losing its collection value.