It depends on its date and mint mark (if any). At a minimum, the silver would be worth about $3 in scrap value, but if the coin has any collector's value it could be worth much more.
Please post a new question with the coin's date and what mint mark it has, if any. On a Washington quarter, the mint mark will be a small S or D above the ER in "QUARTER".
If it's a Standing Liberty quarter, the mint mark will be on the front of the coin to the left of and slightly above the date.
Coins made in Philadelphia before 1979/80 don't carry mint marks, so don't be concerned if your coin doesn't seem to have one.
$3.00
Assuming it's an American quarter, it's worth $3 for the silver in February 2018.
Going purely by melt value, a U.S. quarter minted before 1965 is currently worth about $5.50 for the silver (as of 11 January 2013).
$10
You don't have a pure silver quarter as the US has never minted a pure silver (99.9% pure or higher) silver quarter. Instead what you have is a 90% silver quarter which would be dated 1964 or prior. The value depends on a number of factors including the date, the mintmark and the condition. But a silver quarter is worth $5-6 in scrap silver regardless of type or condition, however some quarters can be worth significantly more.
$3.00
Assuming it's an American quarter, it's worth $3 for the silver in February 2018.
No "quarter silver dollars" have been made by the U.S. Mint. Please post new question. Is it a quarter or a silver dollar?
Going purely by melt value, a U.S. quarter minted before 1965 is currently worth about $5.50 for the silver (as of 11 January 2013).
The 1970 Washington quarter was NOT struck in silver.
A 1953 quarter contains some silver. If it is circulated it is worth $3.66. If it is uncirculated it is worth $4.13 to $4.30.
$10
silver content in 1867-1967 Canadian quarter
It's a novelty item worth couple of cents for the gold plating plus whatever the underlying quarter is worth. If the quarter is copper-nickel, then it's only worth a quarter. If it's a special silver "prestige" quarter made in San Francisco it's at least worth maybe $3.50 for its metal content.
1966 Canadian quarter is 80% silver and approximately has .1501 Troy oz of silver. So it depends what silver spot is. With silver at $48/oz it's worth $7.20
This quarter is not made of any silver so a 1970 quarter is only worth 25 centsIt's a common coin, still in circulation, has no silver and is just face value.
At present, one is worth around $4.