Its a C96 also known as a 'broomhandled mauser' chambered in .30 mauser, they were also chambered in 9mm Luger.

Its a very unique pistol, its fed with a 10 rd stripper clip.

You don't need to register them unless you live in one of the socialist states: NJ, NY, Mass, Ca, etc. If it were illegal to own where you were at, I'd advise not turning it in, but finding a buyer for it in a state where it is legal- it'd be a shame to have a piece of history like that melted down. Oh, and I wouldn't take anything less than $1200 for it if its in decent shape, double that if its in really good condition.

Neat sidenote- a lot of surplus guns were used in the making of Star Wars- Han Solo's blaster was a C-96 Mauser