Thomas Jefferson is not currently, nor has he ever been, on the U.S. quarter. What you probably have is the Jefferson presidential dollar from 2007. It's worth one dollar.
Not much about 25 cents worth it's plated.
It is only worth 25 cents and in no longer spendable.
Please rephrase question.
Since it is gold plated it is considered an altered coin and is worth face value.
It is only gold plated. Since it is gold plated it is an altered coin and is worth 50 cents.
No, they are worth no more than the metal (or face) value of the coin, the gold plating adds so little gold that it would cost more to de-plate the coin than the gold is worth. For example, a 1965 gold plated half dollar would be worth ~$4.50 in silver scrap just like a normal 1965 half dollar. A 2002 gold plated quarter would be worth just a quarter, just like a normal 2002 quarter.
because he was a woman
It would be an unbelievably priceless error coin because Thomas Jefferson's picture is on all nickels minted since 1938. Washington is on the quarter.
There's no such coin as a Jefferson quarter. Jefferson is on the nickel. If you have a quarter the portrait shows George Washington and the coin is worth about 0.18 times the current price of silver. If you have a nickel it's only worth 5 cents. It isn't a key date and it isn't made out of any precious metals.
A 2004 nickel is worth 5 cents. A gold-plated '04 nickel is worth whatever someone is willing to pay for it. There is no standard market value for modified coins like that.
That's Ben Franklin, not Thomas Jefferson, and it's worth about $13 as of 28 Feb. 2012.
July 24, 2009 Gold plating a coin destroys its numismatic value. The Bicentennial quarter is worth but a quarter plus the value of the bit of gold used to plate it.