US Proof Set No "S" Question

There were actually two sets of Proof Coins for 1971. I do not know if it was by design or by mistake, but one set had the S mint mark and the other had no S mint mark on the dime and possibly not on the nickel as well. Thats what I have been able to find so far but I will keep looking.

Hope that helps,

Mike

Also in 1990 there were a handful of proof sets that didn't have the S mintmark and the set is quite valuable.

The full list of error proof sets that may contain a coin missing the S mintmark are:

1968 dime (second rarest no S coin)

1970 dime (estimated mintage 2,200)

1971 nickel (estimated mintage 1,655)

1975 dime (only two sets known. This is the rarest of the no S coins.)

1983 dime (this is the most common of the no S proof coins.)

1990 cent (estimated mintage 3,555 The no S cent can come in either the regular or prestige proof set. Most commonly seen in the Prestige set. Beware of these sets on ebay I have seen a lot of "no S" Prestige sets that have been opened and the proof cent replaced with a business strike Philadelphia coin. The border case on the Prestige holder hides the fact that the inner holder has been opened. For some reason the 1990 no S sets are much scarcer than their estimated mintage implies they should be.)