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Cleaning of old coins
The purpose of this message is to acquaint interested readers with the most simple and safe methods of cleaning coins, which the author can recommend based on his many years of experience in the restoration of an archaeological metal at the State Hermitage Museum. Clearing coins is one of the crucial types of restoration, it is important for their study, dating, identification and storage. Ancient coins made of silver and copper alloys, found in treasures or in other archaeological excavations, most often enter the restoration workshop highly corroded, and sometimes completely mineralized. Under the action of water and salts, copper is destroyed in the soil to form green carbonates and chlorides, red cuprous oxide and black oxide. Continue reading