Many American coin collectors can * certify their coins in independent testing services such as NGC * , PCGS or ANACS * . In addition to the authenticity and the degree of preservation of the coin being tested is confirmed. A special feature of this so-called grading process is the subsequent sealing of the coin in a special square coin capsules ( Slab ) or LIGHTHOUSE EVERSLAB . The " Slab " contains in addition to the coin being tested and the certification information. Due to the special design of the " slab " , the capsules can not be opened again thereafter without zustören the capsule. For Zewcke anti-counterfeiting measures , the capsule also has various security features such as a hologram as well as a watermark . The certification is registered with the respective Institute and can be checked online via the identification number also .
(NGC : Numismatic Guaranty Corporation PCGS : Professional Coin Grading Service , ANACS : American Numismatic Association Certification Service . )