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Potential pattern coin Registry sets are evaluated on a case-by-case basis. Most patterns were struck in very limited numbers and in many cases it is not possible to define a "complete set." Accurate values and rarity estimates are also difficult--if not impossible--to compile, which can prevent a set from having accurate scores. We do, however, offer Custom Sets in the NGC Registry, which allow you to choose what coins constitute a set. This allow collectors of all types of coins, tokens and medals the opportunity to showcase them in the NGC Registry.