The Longacre obverse without stars combined with the 'Standard Silver' reverse of 1870. This design was apparently implemented by William Barber after Longacre's death in 1869.
These were sold as part of complete sets from the half dime to the silver dollar. To view the set, click here.
Examples were struck as follows:
Silver J1059/P1194 with about a half dozen known
Copper J1060/P1195 also with about a half dozen known.
Aluminum J1061/P1196 with only 2 confirmed as follows:
1) J. Flynn in August 1971, Bass, HWBRF-B/M5/99, Superior 1/04, southern collection, Simpson - PCGS64, illustrated above
2) Sieck-81 ANA