This is from their site:
NCS accepts for evaluation all certified or raw coins, tokens and medals. NCS can remove contaminants such as PVC, soils, tarnish, carbon spots, verdigris and encrustation from the surface. NCS does not perform repairs or mechanical alterations of any kind. Removing detrimental material from the surface of an item may dramatically improve its appearance and eye appeal. This service is designed to further preserve the originality of the material only and prevent the damage that can result from contamination that is left untreated.
NCS accepts for evaluation all certified or raw coins, tokens and medals. NCS can remove contaminants such as PVC, soils, tarnish, carbon spots, verdigris and encrustation from the surface. NCS does not perform repairs or mechanical alterations of any kind. Removing detrimental material from the surface of an item may dramatically improve its appearance and eye appeal. This service is designed to further preserve the originality of the material only and prevent the damage that can result from contamination that is left untreated.
swcoin.ecrater.com





















