Among the currently issued commemorative coins, they can be broadly divided into two categories, namely precious metal commemorative coins and circulating commemorative coins. Among them, the materials of circulating commemorative coins are copper-nickel alloy, purple copper and nickel-plated steel core. How much do you know about the maintenance of circulating commemorative coins? Let's learn it together below.
As a metal product, commemorative coins must have higher requirements for the humidity in the environment. Therefore, when preserving the coins, you must pay attention to the environment in which they are stored, either in a moderate sized box or in a vacuum plastic bag, to avoid excessive contact with the air as much as possible.
Second, anti-acid and alkali
Acid and alkali substances and metals put together will produce a chemical reaction and cause a high degree of corrosion to the commemorative coin, so it is important to keep away from acid and alkali substances during long-term placement.
The bumping of the coin surface will inevitably cause damage to the coin's graphics, affecting the beauty and mood of the collector. Therefore, you should wear gloves during the appreciation process; during the storage process, you should also try to hold it lightly and keep it away from hard objects.
In addition, since coins in circulation usually lack packaging, such coins should first be wiped with a soft dry cloth before collecting and then stored in a box. If not stored properly, some copper coins will have a copper green color on their surface in a humid environment. To remove this patina, do not wipe vigorously after it is dirty! Although it may seem beautiful for the time being, and a magnifying glass of 40 times or less will not reveal the problem, it will cause minor damage to the surface of the coin, and this damage will aggravate the oxidation in the future!
Four, anti-sweat stains
When viewing or playing with coins, you should wear standard gloves or use professional tools.
Remember not to touch the coins directly with sweaty or wet hands, as sweat and other liquids may cause corrosion to the surface of the coins.