1805 is a fairly valuable date for US dimes so you should have it authenticated by an expert. Numismedia lists the following approximate retail values as of 08/2014:
Very worn condition - $690
Moderately worn - $1,230
Slightly worn - $1,740
Almost no wear - $4,336
Uncirculated - $6,560 to $63,050 depending on quality
DISCLAIMER: The retail values quoted are the best available as of the date shown, but may vary significantly due to changes in the precious metals market. Also the wholesale (buying) price of a coin will be less than the selling (retail) price. A reputable coin dealer will be able to give a more accurate valuation based on inspection of the coin.
$100,000,000
The value of a US dime marked "ten centavos" is zero, since it is a fake. A real US dime is marked "one dime," not "ten centavos."
a 1917 us dime is called a mercury dime. its not that rare so it is worth about a dollar
Face value only.
The US discontinued its half-dime denomination in 1873.
what is the value for an American 1909 silver dime
$100,000,000
The value of a US dime marked "ten centavos" is zero, since it is a fake. A real US dime is marked "one dime," not "ten centavos."
a 1917 us dime is called a mercury dime. its not that rare so it is worth about a dollar
A 1988 dime is worth 10 cents.
Face value only.
10 cents
10c
The US discontinued its half-dime denomination in 1873.
The 1965 dime is a Roosevelt dime. This dime does not carry a mint mark and there were 1,652, 140,000 of them minted in the U.S. They have a value of between 10 cents and 2 dollars.
A US dime dated 1944 is a Mercury head dime, it's very common with a value of $2.00 just for the silver.
The British have never produced a "Dime" coin. The "Dime" is a US 10 cent coin.