1.78 grams 1873 1893 1909 1910s 1934 1936 lincoln cent 1942 1955 1955-s 1957 1959-d lincoln cent 1961 1964 1964 cent 1964 d 1967-d 1968 1969-s/s 1970 1970s 1971-d 1971-s 1972 1991 lincoln cent 1993 2006 2008 2018 acid attribution barber broken l cent chile circulated clo-002 clump commemerative cud d/d/d damage ddo ddr denver dime education error jefferson lamination lincoln mark minor mouth pennsylvania penny peru photos proof quarter rpd rpm rpm003 study urs varieties variety virginia vna washington