San Francisco has made dimes for well over a century so the mint mark isn't enough to go on. Please post a new question with the coin's date, or enter the question "What is the value of a <date> US dime?" in the large box at the top of this page. <date> is of course your coin's actual date.
The mintmark can only be a "D" for a 1960 dime. Regardless it's so common the value is $2.00 just for the silver.
The W is not a mintmark. It is the designers initial. The possible mintmarks are D or S.
The W is not a mintmark. It is the designers initial. The possible mintmarks are D or S.
Current retail value is $5.00. Issue price was $11.00. But look at the dime. If it has no S mintmark the the value jumps to about $1,000.00.
For a 1964 dime, only a "D" mintmark is possible, so many were made that value is just for the silver, about a dollar.
Assuming the coin is circulated and has no "S" mintmark, the 1915 Barber dime is a common date, retail values are $4.00-$8.00 for most coins.
A circulated Seated Liberty dime without an "S" mintmark dated 1889 has retail values of $10.00-$80.00 depending on the condition of the coin.
A 1970 Uncirculated Mint set would not have a dime with a "S" mintmark, only a Proof set will have a dime with a "S" mintmark for that year, so no your mint set is not rare.
Please look at the mintmark again. The Denver Mint did not exist in 1873, the only mintmark's it could have are "S" or "CC". Post new question.
I also have a 1917 s mercury dime it appears to hace dubbling on the B ,,,as most will tell tou uts worth as much as someone is willing to pay!
No rare 1941-S dimes. The 1941-S Mercury dime does have large and small mintmark varieties as do all coins (except the half dollar) that were struck in San Francisco in 1941, they have no added value.
No such coin exists, 1964 dimes were only made in Philadelphia (no mintmark) or Denver (D mintmark). Both are incredibly common and only worth about $2.25 for their silver scrap value as they are 90% silver.