Try This at Home: DIY Geodes

By OSC on June 21, 2018 in What's New


  • Seashells
  • Scissors
  • Glue (any basic school glue will work)
  • Small paint brush
  • Alum powder (found in the spice aisle)
  • Water
  • Heat-safe container (coffee mug works well)
  • Food coloring
  • Spoon
  • Measuring cup
  • Saucepan




Part 1
  1. Collect some open-face seashells.
  2. Use the paintbrush to spread a layer of glue over the inside and around the edges of each shell.
  3. Sprinkle a generous amount of alum powder over the glue while it’s still wet.
  4. Gently shake out any extra alum powder and let the glue dry completely.


Part 2
  1. Heat 2 cups of water to just below a boil and stir in about 40 drops of food coloring.
  2. Add ¾ cup alum powder to the water and stir until the powder has completely dissolved.
  3. Let the solution cool for 30 minutes.
  4. Submerge each dry, alum-coated shell in the solution, allowing it to rest on the bottom of the container with the inside of the shell facing up. Leave at least 2 inches of solution above the shells. Let sit for 24 hours.


Part 3
  1. Use a spoon to carefully remove the seashells from the solution and place them aside to dry completely. Enjoy your creation!

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