It's not clear what you mean by "great", but in numismatic Very Fine condition (minor wear, but all details clear and sharp) an 1879-O dollar would retail for around $18.
$2 to $3 in average condition
Depending on condition $20 to maybe $60, a little more if the case is original and in real nice condition.
Based on the research done on eBay (March 2012), An Austria-Hungarian Silver denier (circa 1540-1600) is worth between $7.00 and $15.00, depending on condition. The coin itself is about half the weight of an silver US Dime. So the silver content would be worth about $1.25 (again March 2012) As with any coin or collectible, condition and rarity have a lot to do with value. There may be variations of this coin that could be worth more.
we have a selmer signet coin silver flute, purchased in 1969, or 1970 do you have an idea of what this may be worth it is in very good condition, and it has the original case
10$ to 25$ 10 dollars if worn a lot. 25$ if is inextremely fine condition.
It is worth about $10 in good condition and about $20 in mint condition.
If great condition is actually Mint State, the retail value of a MS-60 coin is about $500.00
It is 40% silver and worth about $5 in scrap silver regardless of condition.
It is not silver, it is copper and nickel. It is worth $2 in high end circulated condition, and $6.50 in uncirculated condition.
A 1969 silver Kennedy half dollar is worth $5 inn perfect condition. The value of the silver is worth $2.87.
Currently as of April 2012 a 1880 Morgan silver dollar in MS63 uncirculated condition is worth around 63 dollars.
In an uncirculated condition, this type would be worth around $90,000.
A 1992 American Eagle Bullion Silver Dollar in MS65 condition is worth: $24.00.
In average condition the coin is worth $15-20.
The 1924 silver dollar is called a Peace dollar because it says Peace on the side with the eagle. It is worth about $25 for the silver alone. If the condition is better, it is worth more.
A 1884 Silver Dollar - aka - Morgan Dollar - is worth in good condition (G4): $18; if its mint state is MS60, the value rises to: $40.
1943 cents are steel and zinc, not silver. They're worth 10 cents in average condition and upwards of a dollar in uncirculated condition.