20. If the finder of any treasure fails to give the notice, or does not either make the deposit or give the security, required by section 4, or alters or attempts to alter such treasure so as to conceal its identity, the share of such treasure, or the money in lieu thereof to which he would otherwise be entitled, shall vest in Government, and he shall, on conviction before a Magistrate, be punished with imprisonment for a term which may extend to one year, or with fine, or with both.