If you are strong enough and are going to be working hard rock, then a 16 pound sledge hammer is best. I use a 12 pound sledge hammer most of the time. If a 12 pound hammer is too heavy for you, don't waist your money on an 8 or 10 pound hammer, buy a short handle heavy masons hammer in 6 or 8 pound weights. They are easiest to use, less expensive and more practical. If you ever are lucky enough to open up a new pocket filled with minerals you will find a long 12 or 18 inch screwdriver the best tools for extracting specimens.
Every experienced collector has one.
Some prefer ice picks, or coat hangers, or plastic tools. But you will need a tool for prying loose and retrieving crystals from deep inside the pocket. A long screwdriver is a good start. If you don't have one of these long pocket tools you will end up with cuts all over your hand from reaching deep inside a crystal-lined pocket and you will inevitably leave behind some crystals that you couldn't extract with just your fingers. An assotment of long tools for extracting crystals from deep inside pockets.