I spray them off good when I get home, then I soak them in bleach and soap water overnight to kill any dead desert lichen, which this stuff has it in every nook and cranny and deep in the quartz crystals clusters so I usually have to go heavy on the bleach, then I pressure wash them good, then I soak them in warm water for a day to leach out any bleach left in the agates, after that I soak them in super iron out (powder kind only) for anywhere from 12 to 48 hours, I check them every now and again to see if they are clean to my liking, then I pressure wash them again and scrub them with a brush, toothbrush for the more delicate ones, after that I soak them for twice the amount of time in fresh water, usually in the tub, changing the water every now and again or a slow leak works to. That cleaning method seems to work well on quartz but I wouldn't recommend it for any other minerals.