Detecting defacement or contamination, e.g. dirt

Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency > Testing mechanical properties or condition, e.g. wear or tear > Detecting defacement or contamination, e.g. dirt

Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency > Testing mechanical properties or condition, e.g. wear or tear (G07D7/16 takes precedence) > Detecting defacement or contamination, e.g. dirt