Very well.. One main issue anyone will face with their collection of rocks/stones, will undoubtedly encounter is the caked on mud issue.. About the only thing I've found that works in sever cases, is several soaking in warm water and 20 mule team borax.. However, don't just let them soak.. One must continue to clean with a tooth brush then soak once again.. This will take time.. After a good soaking for several weeks.. You can move onto the next stage, using dawn foam.. Which actually foams up on the stones thus lifting up any excess left that one couldn't clean. I have heard of chemical treatments which can harm your crystal and stones.. In some case "its better to leave things as they are" or risk damaging the stone.. Lastly.. If the stones have a good size and shape to them.. A tumbler would;d be a great thing to clean them.. A mild solution of (borax) and a few stones in the barrel and allow it to tumbler for about 2 weeks checking the barrel once every few days..