Although mint records do not indicate that any were produced, nine examples of the 1870-S Seated Liberty Dollar are known to exist. The original mintage is presumed to be 12 pieces, making this issue without a doubt the rarest of the series.
It is believed that the 1870-S Silver Dollars were struck for the purpose of making a time capsule for the San Francisco Mint. Plans had been made to include a complete set of denominations when the cornerstone for the new building was laid on May 25, 1870. Presumably, more than one example of the silver dollar was struck, since they would make suitable keepsakes from the ground breaking ceremony.
As mentioned, there are only nine examples of the 1870-S Seated Liberty Dollar confirmed to exist, with another example believed to remain within the time capsule placed at the cornerstone of the San Francisco Mint. Of the nine, two have been graded MS62 and the others show signs of circulation or damage.
One of the finest known pieces from the James A. Stack sale conducted in 2003 realized $1,092,500. An example graded PCGS XF40 sold for $503,125 in 2009.