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Did you know…

A mummified frog was discovered in a flint geode in 1899!

Activity: Make your own “geode”

It may take thousands of years for a real geode to form, but with this activity you will have crystals growing in just a few days!

The following sites will explain how to grow your own crystal “geodes”:

Crystal Geode Project
Make a crystal geode with alum, hot water, clean egg shells or plaster of Paris, and food coloring

Make your own Geode Egg
Make a geode with borax, hot water, clean egg shells, and food coloring

We made a variety of “geodes” using sugar, salt or alum and poured each solution into clean egg shells.

Here are the results of our experiment:

Picture 1: Salt “geode”

Picture 1 We added green food coloring (made with blue and yellow food coloring) to a salt solution and poured it into a clean egg shell.
As you can see the colors separated! It was very interesting to watch. We allowed the solution to evaporate on its own which took a couple of weeks. 

Picture 2: Alum
Picture 3: Alum


Pictures 2 and 3 This solution was made with alum, a pickling spice, and it made crystals that look like a hexagon. Each one took a couple of weeks to become what you see.
Picture 4: Sugar

Picture 4 This solution was made with sugar and blue food coloring. Our solution was very saturated and as the water evaporated, it looked like a thick tar-like syrup! 

Note: Results may vary.

Tip: Be sure to make a super-saturated solution so that your crystals will grow.

Question of the day:

How does a geode form?

Learn more:

Rock Frogs
Find out how a frog winds up inside a rock!

About: Geology
Offers information about rocks, minerals, geology basics, maps, quakes, earthquakes, landforms and more.

Wikipedia: Geode
Learn how geodes are formed, coloration, and where they can be found.

United States Geological Survey: Research and monitoring, news, and much more.

News and Information About Geology and Earth Science

An international initiative of the geological surveys of the world.

OneGeology – Kids
Find out what geology is, learn about geological maps, rocks and minerals, earthquakes, volcanoes, and much more, with cute little character icons to guide the way.

Rocks for Kids: Geode
Gallery of geode pictures and facts.

Fossils – Facts – and – Finds
According to the site, they offer inspiration and fun to kids who are interested in rocks. There are teacher’s resources offered such as earth science lesson plans, coloring page
s, activities (puzzles), fossils, and other things.

Geology for Kids
An in-depth online geology textbook written for kids.

Geode Match – Game
Match the geodes before your time runs out! – Rock & Mineral Resources
Long list of rock and mineral resources.

Connect with!
Pink geode by Fran W.


  1. I think several of us had rocks “on the brain” this past week! LOL Great post!

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