You’ll find geodes with agate and quartz crystals and amethyst (rare) at walker valley. You are digging in a hardrock quarry, which is occasionally a working quarry. With the help of their dynamite and heavy equipment new material is exposed, which makes it easier to find things. Otherwise you will need a sledge hammer, pry bars and chisels ect.. You can also look in the Talis slope for easy pickings. See Washington State Mineral Council for field trip information.