EASY METHOD: Simply wash the geodes in plain water with a bit of laundry detergent (or dish soap), then let them soak in a tub of water with 1/4 cup of ordinary household bleach for two days. This cleans most of the heavy grit off the geodes.Click to see full answer. In this regard, how do you polish a geode? Polish your rocks. Use a heavier fabric like denim to add a commercial finishing polish to your geode. Rub down the geode gently until it’s as shiny as you want. You can buy commercial finishing polish for gems online or at some hardware stores.One may also ask, how do you make river rocks shiny? Wash the rocks with soap and water and let them dry. Then oil the river rocks with jojoba oil or cooking oil to give them back their wet look. After some minutes wipe off excess oil. Now the river rocks are more colorful and shiny. Likewise, how do you clean raw crystals? Soak the crystals in a bowl filled with water-diluted bleach and let them sit for several days. Be sure to rinse the quartz crystals well after taking them out of the bleach solution. Let the crystals dry thoroughly (for at least one day) before you begin any other kind of chemical cleaning. Can you put geodes in a rock tumbler?Throw a geode in the tumbler and it will be toast. If you must experiment, do so with a cheap bits of Brazilian amethyst geode; the crystals will wear off leaving the greyish banded quartz rind, which is much tougher. So if I have nowhere to display them it’s no use to have them.