Given the limited numbers produced at each facility , they might have been hoarded as collectibles .
The circulating cents struck in the 1980s at San Francisco ( except proofs ) and West Point also bear no mintmark , as their facilities were used to supplement Philadelphia 's production .
Given the limited numbers produced at each facility , West Point might have been hoarded as collectibles .
The circulating cents struck in the 1980s at San Francisco ( except proofs ) and West Point also bear no mintmark , as their facilities were used to supplement Philadelphia 's production .