When any person presents to any pawnbroker for the purpose of pledging the same as security for a loan, any implements or tools commonly used by mechanics, the pawnbroker shall require such person to give proof that he is the owner of the tools so offered as a pledge, and when the tools so offered are stamped with a name or any initial or symbols the pawnbroker shall require the person offering such tools or implements to produce the stamp by which such name, initials or symbols were imprinted, or if unable to produce such stamp such person shall be required to establish his identity.