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numismatics ultrasonic testing
超声波探伤法:近来市场上发现不少造假手段极其高明的赝品,例如用两枚普通真币合并成一枚价格较高的合背或合面钱;运用现代微型磨床和微型铣床将一枚真的普通币加工成另一种珍品。"魔高一尺,道高一丈",采用超声波声像仪,可看清钱币的内部结构,改刻、挖补、拼合等伪作的钱币便无法藏身。