‘I’m not a Scientist..!’ – Crystals Activity 1: Egg Geode

By Farhin Begum

Hello to all you scientists and non scientists!

You’re probably wondering why this is entitled ‘I’m not a scientist’  …working in a science environment, as science made simple’s trusty receptionist with no science background has got me thinking “Hey! Maybe I can give this science thing a go, it won’t be so bad” (you can be the judge of that!) – Hopefully you’ll be joining me in my journey in trying out science experiments that I will be testing for you guys!

My first experiment is part 1 out of 3 different activities on CRYSTALS – no, not Breaking Bad style!

 Egg Geodes


All rights reserved – Magical Daydream – Mariëlla


Look how awesome this DIY geode looks! I’ve always thought that crystals are cool, so for my first science experiment I decided to make some! These are made from a chemical called alum powder, and egg shells.

<<<<<<<<This is what we are aiming our egg geode to look like! Make sure you read to the end before giving this a go – my attempt didn’t quite turn out as planned!



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You will need..

  • Towel
  • Bowl
  • An egg or two (white eggs if possible!)
  • 1 cup or hot water
  • PVA glue
  • Plastic cups
  • Food colouring (egg dye!)
  • Alum powder
  • A plate
  • Scissors
  • Paintbrush
  • Table spoon
  • A drawing pin


Step 1 – Pin Up…

pin in egg

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First of all, select the best looking eggs for your picture (and of course your activity) then slowly stick the drawing pin through… make sure you do them in both ends and trust me the eggs aren’t as fragile as they look, but don’t poke them to hard – they’re just eggs after all.


Step 2 – And Blow!


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I suggest you wash your egg before you blow the yolk out of it, it can get very messy!


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After struggling for 10 minutes I inserted the drawing pin again and made the hole into a little straight line, after that things went very smoothly.




Step 3 – Split In Half?


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When you think your egg is empty, grab your scissors and start cutting through one of the holes and cut round until you have two halves. After you’ve successfully done that gently wash and wipe the egg then leave it to dry overnight.



 Step 4 – Glue, Sprinkle & Tap Off


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Now get your paintbrush and PVA glue and start applying it on the inside of the egg. Then sprinkle the Alum powder over the top then tap off the excess.



Step 5 – Careful it’s HOT!


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Boil some water then fill one plastic cup up just below the line. Now add your choice of food colouring (I put in about 3 caps-full of red food colouring) then add 1 table spoon of Alum Powder and stir, stir, stir!


Step 6 – Sinking


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Now add in your egg (one egg per cup) and push it down with your table spoon so it sinks to the bottom of the cup.





Step 7 – Red, Purple & Blue!


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Leave your cup over night in an environment that won’t be disturbed. Here I made 3 different egg cups – red, blue & purple.






Step 8 – What a FAIL!


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So as you can see… It was a FAIL! Yep, the experiment didn’t work as planned – It was wet and soggy and most of it was just nasty looking glue! But on the bright side the egg shell turned in a cool teal colour.



After this fail attempt of this egg geode experiment I have gone back and researched on what I did wrong. Apparently you would need white eggs for a more effective results and egg dye! Yes, egg dye instead of food colouring! You can buy egg dye online but because I live in the UK it is pretty hard to find white eggs in your local supermarket but if you like you can just go to your local chicken farm.

I also needed to leave my eggs in for longer, and could have added even more Alum powder for a more successful result.

Send us your pictures of your egg geodes, I hope you have more success than me!crystal note



All rights reserved – Magical Daydream – Mariëlla

For a more a successful result check out this blog by a lovely girl, Mariëlle – Magical Daydream








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Posted in Activity, Chemistry, Exploring Science, Geology
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