If it's a 1973-S, that makes it a proof coin that was sold to collectors instead of being released for general circulation. Silver proofs contain 90% silver.
It is a common coin and only worth 1 cent.
is wm rogers sliver ware marked I S
The 1973 proof Eisenhower dollars were struck in 40% silver clad and copper-nickel clad. Average retail value of the CN coin is $7.00, the 40% is $14.00.
Assuming the coin is circulated, the 1880-S Morgan is a high mintage common date, retail values, as of 4-20-11, are $38.00-$44.00 depending on the grade of the coin.
8-3-11>>> The 1973 Kennedy half dollar is very common, still in circulation, contains no silver and is face value, unless it's a "S" mintmark Proof coin or a very high grade Mint State coin.
A 1973-S proof set is worth from $12 to $15.00.
The value of a coin from the 1600's or any other time period varies, depending on the condition of the coin. They can be worth as little as $10 or their value may be in the thousands of dollars range.
There's no way to answer that without knowing which denomination. A '69 nickel is worth a different amount than a '69 half dollar.
More information is needed. Please post a new question with the coin's denomination, country of issue, and any other details that might help ID it such as the image(s) and/or wording on it.
S
This is a on-line value guide NumisMedia.com or buy a copy of Red Book
Assuming the coin is circulated and has no "S" mint mark retail value are $312.00-$420.00 depending on the grade of the coin.