It sounds like what you have is a privately minted bullion coin that is meant to look like a US Seated Liberty dollar from the mid 1800's. If it is in fact silver, it is likely worth no more than the metal value of the coin (silver is trading at US$35.30 per troy ounce as of midday on March 4, 2011). If it is not actually silver, it probably has very little value.
A $10 Liberty gold coin weighs 16.718 grams or 0.5376 troy ounces.
It's not a coin, it's a bullion piece or "round". Its value is tied to the spot price of silver, currently about $12-$13 per ounce.
There is a real Bill of Rights coin but it is a commemorative coin minted in 1993. Since yours has a 1991 date and "one troy ounce .999 fine silver" on it, I think you probably have a bullion coin and it is worth whatever the silver in it is worth on any given day.
From your description this is not a US Mint product, it's a privately minted replica of the 2001 American Buffalo silver dollar, the value is for the silver only, about $26.00.
The $50 Liberty is a bullion coin valued for the one troy ounce of gold it contains. Current price would be $1200 - $1400, depending on the spot gold market.
The amount of pure gold in the coin does not equal an ounce, the Actual Gold Weight (AGW) is .48375oz. The total weight of the coin is 16.718grams.
Yes, if it has the word "COPY" on it, it is a fake coin.
1945 Est. 140,000 minted Value: Bullion Value +20% contains 0.0482 Troy oz. of gold
What you have isn't a US coin, but rather a privately minted silver bullion round. It is worth whatever 1 troy ounce of silver is worth, at the time of writing it is worth about $34, but the price of silver fluctuates, sometimes wildly, so tomorrow it will be worth more or less.
It is worth whatever one troy pound of silver is worth. Since 1 troy pound is 12 troy ounces and since one troy ounce of silver is worth ~$22, your coin is worth $264. However, keep in mind that silver prices fluctuate on a minute by minute basis.
Actually it's Liberty walking not standing. It's one (Troy) ounce of silver with a current values of $34.86.