Preserving Metal Coins

Conservators and archivists, as well as museum curators, use several best practices to mitigate the effects of corrosion, improper handling, excessive humidity, and air pollution on metal coins. For example, they can regulate the indoor environment's temperature.

 

Conservators, archivists, and curators should keep the humidity between 40% and 55% to prevent corrosion. In addition, they can use dehumidifiers and air conditioning to mitigate the environment's moisture levels, according to the AIC's advice on caring for metal objects. Similarly, the temperature should be maintained between 68° F and 70° F.

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Similarly, covering metal coins with dust covers and monitoring the environment for any signs of dust and air pollution will ensure the longevity of these treasures for present, as well as future, generations.

 

In addition, archivists may use light exposure strips, as well as hygrometers, to check for indicators of atmospheric pollution and protect the coins. Clean, safe, environments are the best way to prevent corrosion from various sources.

 

Metal coins need to be stored alongside non-moving materials. The AIC recommends that conservators and archivists should place coins in metal cabinets and on metal shelves. Wooden cabinets and shelves, conversely, release corrosive gases and acids. Moreover, acid-free wrapping paper and boxes, as well as clean, smooth cotton fabric, are ideally the best storage tools.

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Conservators and archivists, in addition to curators, can purchase "silver cloth" from jewelers' and fabric stores. This type of material will prevent the rate at which silver tarnishes by hindering sulfur in the air from settling on the coins' surfaces. In addition, the softness of silver cloth prevents scratches while its thickness simultaneously protects metal coins from dents and breakage. When handling coins, conservators and archivists should use clean, white gloves to prevent further damage. 

 

Silver fabric needs to be changed every few years to prevent tarnishing, as washing and re-use are not suggested. Furthermore, housings, which are storage containers, can provide suitable protection for the coins, and should be filled with silver cloth. 

 

Storing metal coins in glass housings filled with silver cloth would be the best option for enhancing their longevity. Coins should not be cleaned, except by an expert coin collector, due to the high risk of damage. Moreover, the tarnish enhances their monetary value and historical worth.

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