Acid Dye Egg Geode




"When we saw this project from Steve Spangler on Martha Stewart's website, we had a hunch that we could substitute our acid dyes in place of the food coloring for an even brighter color. A little experimentation revealed that our guess was correct. Our acid dyes are perfect for creating brilliant and vibrantly colored crystal eggs. Today we share this project, adapted for use with our Acid Dyes."

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Step 1: Let's Get Started

Shopping list:

Half an egg shell

Jacquard Acid Dye or Dharma Acid Dye

Alum powder

White glue

Small paintbrush

Craft stick or spoon

Rubber gloves

Drying rack or newspaper

Step 2: Create Your Own Colorful Geode

1. Carefully crack an egg shell in half just as you would when cooking. *Make sure the inside of the eggshell is clean and dry.

2. With a small paintbrush, apply white glue to the inside and cracked edges of the eggshell half, and sprinkle with alum powder until completely coated. *Set aside to dry overnight.

3. The next day, prepare growing solution in a glass or plastic container by using a craft stick or spoon to mix 2 cups of very hot water (almost boiling) with ¼ tsp of Jacquard Acid Dye.

4. Add 2/3 cup of alum powder to the hot dye bath and stir until completely dissolved. If there are remaining crystals in the bottom of the container, place the solution in the microwave for a few minutes to dissolve them. This will prevent alum from being drawn away from the geode.

5. Once the alum is completely dissolved, let the solution cool slightly for about 30 minutes. Submerge the dried, alum-coated eggshell in the growing solution, allowing it to rest on the bottom of the container with the inside of the shell facing up.

6. Set the container aside in a safe place overnight to allow the crystals to grow undisturbed. The longer the eggshell is in the solution, the larger the crystals in the geode will be. Twelve to 15 hours will usually result in a perfect geode.

7. The next day remove the geode from the growing solution very carefully(as wet crystals are quite fragile). Be sure to wear latex gloves to prevent the dye from staining your hands.

*If you are not satisfied with the size of your geode crystals, return the geode to the growing solution and wait a day or two. As water evaporates from the solution, more alum will be deposited in your geode, increasing the size of the crystals.

8. Place your geode on a drying rack or newspaper. Allow to dry completely before handling.

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    13 Discussions


    5 years ago on Introduction

    These are beautiful. What prevents the outside of the shells from getting coated, or if I wanted to, could I glue the alum on the outside and have crystals inside and out?

    3 replies

    Reply 5 years ago on Introduction

    I think that the inside of the shell is 'seeded' when they sprinkle the dry alum on the glue. This gives the alum in the solution a base crystal to grow on. If you wanted crystals inside and out, then you would need to glue and dust the outside as well, as far as I can tell anyways.

    Yes, exactly. Sorry we weren't clear the first time. You would glue and sprinkle the outside so crystals would grow there too, if that's what you wanted.

    Otherwise, be careful you don't get glue and alum on the outside or you'll have crystals where you don't want them!


    Reply 5 years ago on Introduction

    jarikcbol, you are correct! You can create "crystals" on the outside by following the same instructions as for the inside!


    5 years ago

    You mentioned that the crystals are quite fragile when wet. How strong are they when dry? Can they stand much handling or are they pretty much things to be put on a high shelf and admired from a distance?
    They are absolutely gorgeous!!

    3 replies

    Hi Izzypup,

    As they are made of a fragile egg shell I think you could handle them a bit when completely dry but then I'd put them up to be admired! Thanks for your question!


    I was actually wondering about the crystals themselves. I thought I might try a different, more substantial 'container' to start the geodes.
    So, are the crystals fairly tough?
    Thanks for your first answer and I'm looking forward to your second!


    Sorry about that, missed the mark the first time!

    While the crystals are sturdier when dry, they are still relatively fragile. A light touch probably won't wreck anything, but i wouldn't hand 'em over to the kids for playtime, so to speak.

    prince link

    5 years ago

    would it be possible to make the crystals different colors by placing them in multiple baths?

    1 reply

    Hi prince link!

    You might be able to do different colors but keep in mind that dyes are transparent and you would be over-dyeing the color dyed first. If you try it let us know how it goes!

    Thank you for your question!