Please post a new question with the coin's denomination and the country that issued it. That information is needed to provide even a ballpark answer.
No one can predict the silver price, otherwise we'd all be millionaires. As a collectable, not much. It is a common coin worth only silver price. So if silver price goes up, the value of it goes up. If silver goes down, the value goes down.
Nobody knows that. But I think the price of silver and gold will drop by then, so the value may be less then today.
The coin has NO silver and is face value.
The US never made silver pennies. It would cost too much for the mint to make them. Your coin is plated silver this adds no value to the coin.
As of today the value is about $17.00 it's a bullion coin and the value is just for the silver. FYI it's called a Silver Eagle or American Silver Eagle coin
If the coin has any wear the value is for the silver about $12.00
Painting adds no additional value to the coin. It is still a bullion coin and most of its value is in the silver it contains. The value of the silver changes almost daily. Currently it is about $17.
If the coin has any wear the value is for the silver, about $2.00
The coin is not a silver liberty dollar. It's a 1979 Susan B. Anthony Dollar coin and has no silver in it and the value is one dollar.
The value of a 1800 silver dime depends on the condition of the coin. In mint condition this coin sells for as much as 2000 dollars as of 2014.
Current value of the silver is $15.40. Regardless of date, all Peace dollars contain .77344oz of silver.
In 1993 the Republic of Liberia issued a Nolan Ryan 10 dollar silver proof coin. The value of this coin is about $15.