What are Geodes?

Geode is Greek word "γεώδης" meaning "Earth-like"

How to grow geodes at home?

You will need:

  • Alum powder
  • Eggs 
  • Glue
  • Small glass containers/jars
  • Hot water
  • Food/egg Dye
  • Pin, Scisors, Paintbrush, Papertowel

How to:

  1. Prepare the egg shell:
    1. Blow out an egg: Make two holes on each of pointy sides, gently blow out the egg
    2. Cut egg into two halfs lengthwise
    3. Clean and dry the inside
  2. Create the crystalisation surface:
    1. Apply glue to the inside of the egg
    2. Sprinkle Alum powder over it, shake off the excess
    3. Dry the shells
  3. Prepare saturated Alum solutuion:
    1. To 1 cup of near-boiling water add gradually 1/2 cup of Alum powder, mix untill all is desolved
    2. If some powder is still not disolved, mictrowave the mixture to rise the temperature - it is important that all the crystals are disolved in the solution, otherwise the crystal formation will happen not only on the eggshell
    3. If you would like, add dye into the solution
    4. Cool the solution down a little bit
  4. Starting to grow the geodes
    1. Place the eggshell into the warm Alum solution, inside part up
    2. Set the jars aside for 12-48 hours
    3. Spy on the growth of your geodes - you can take them out of the solution, but be careful with wet crystals they are more fragile
  5. Finishing your geodes growth
    1. When you are happy with the geodes, take them out from the solution and place on the paper towel
    2. Share pictures of your geodes with us via Twitter @Scientist_ND and Facebook @scientistND
    3. Pro Tip: If you want to prserve your geodes for longer and prevent the wear and tear associated to normal humidity and handling, you can coat the well dried geode crystals in transparent nail varnish