Years Issued :                       1964 (90% Silver), 1965-1970 (40% Silver)
Mints:                                       United States Mint at Philadelphia, Denver, San Francisco
Mintmark:                              No Mintmark, D, S
Weight:                                    12.50 grams (1964), 11.50 grams (1965-1970)
Diameter:                                30.60 mm
Edge:                                         Reeded
Composition:                        90% Silver (1964), 40% Silver (1965-1970)
Total Estimated Mintage: 429,509,450 (1964), 848,895,006 (1965-1970)
Obverse Design:                  Gilroy Roberts
Reverse Design:                  Frank Gasparro