Q: I have inherited a mining stock certificate from my grandfather. How much is it worth?

In general the stock probably is not worth anything. If the company listed on a stock certificate was incorporated in Arizona or the Arizona Territory, you can determine if the company is still active, or how and when it became inactive, by calling the Arizona Corporation Commission at 602-542-3026. They provide basic information on incorporated companies. You may obtain this information by sending a fax detailing the company to the Arizona Corporation Commission at 602-542-3414.
If the company is inactive or the stock cancelled, an original certificate in good condition may still be of trivial value to collectors of mining memorabilia.