SilverMarc SilverMarc is a geocacher from New York City. Like his namesake, the geocoin is all silver. According to the geocoin, he is located on West 70th Street, less than 250 m from the western side of Central Park. Size: 39 mm | Weight: 26.8 g on Wednesday, 14 February 2007. Posted in GEOCOINS, Personal, Non-Trackable, Mostly Metal < Prev Next >