Basic requirements for custom metal commemorative coins
MetalCommemorative coin CustomizationThe basics of Kimbiban are usually corrosion-resistant; Silver is corrosion-resistant to copper; and metals such as zinc, aluminum and iron are more susceptible to corrosion. For alloys, it is sometimes dependent on metals with a more vivid chemical properties, such as pure gold, and when copper is added to the gold to form an alloy, it is easy to present black dots on the coin.
But brass (copper and zinc alloys) is more corrosion-resistant in the atmosphere than pure copper. PVC is harmful to coins in packaging materials, and substances such as water vapor, sulfide and carbon dioxide in the air are also harmful to coins, such as sulfur and silver response to silver sulfide, so that the surface of silver coins become gray and black. Moisture in the air also accelerates the oxidation process of coins. In the appreciation process, touch the bare coin with your hands so that the sweat leaves fingerprints on the coin, and the dust in the saliva and air lands on the coin, which will speed up the corrosion process of the coin.
Choosing a packing method is the basic skill of a coin collector. Generally speaking, the optional packaging has non-polyvinyl chloride plastic box, with polyester film round hole of the paper, polyester film bags, paper bags and so on. Optional data are polyethylene, polypropylene, polyester film. In order to facilitate appreciation, can also be placed on the basis of bright packaging in the collection coin book, the key point is that can not choose PVC-containing data to wrap the storage of coins, its harm must not be underestimated. In order to block air, there are generally two methods of gas tightness and vacuum encapsulation.
Airtight refers to air that blocks air but does not suck in the packaging. Vacuum packaging allows packaging materials to be tightly touched on the surface of coins, which may also harm coins. The simple way to block the air is to soak the coin in anhydrous alcohol, the disadvantage of this method is not easy to see, but the effect is better. It is generally not appropriate to touch bare coins directly, especially if you should not touch refined coins, illiquid coins (UNC) or high-end coins. Coins in the hand touched by the local, must be the first corrosion and blackening of the Local. If you want to take a coin, apply a clean soft paper or cloth to take the edge of the coin from the other hand. Metal commemorative coins generally do not need to be cleaned, if dirty, just need to put it in warm soapy water to clean, and then wash with water, put in two soft cloth to suck dry water can be. High Silver silver coins if only by slight oxidation, with ammonia solution plus sodium carbonate solution and toothpaste tone into a paste to clean, or with edible white vinegar to a small amount of water, the silver coin into its solution soaked for a few minutes, can also be used cotton ball dip solution gently wipe the coin surface, to the coin surface oxidation layer dissolved, wash clean with water.
Metal Commemorative coin Cleaning Precautions:
First, can not use the strong sulfuric acid, nitric acid solution;
Second, can not use toothbrush, sand batch paper, such as scrubbing;
The third is to wash the residual decontamination solution and dry the coin. Not as a last resort, do not easily clean gold and silver coins, if you really need to clean, please mint or distributor professionals to take care of.