Looks like a .25ACP Mauser 1910. A very nice pistol, but not very collectible. I see them at the shows now and then for between $250 and $400. The most common wear seems to be to the grips, and they are a bit difficult to find in good condition. Barrels are usually rough too, so a good bore is a bonus.
This one seems to be in above average condition though, and the holster should add a bit to the value as well. Is it yours or are you planning to buy? These little guns may not be the hottest on the market, but they are very well made and they're a blast to shoot as well!
