Thursday, May 20, 2010

Eggshell Geodes: The Longest Science Experiment Ever.

Where, or where, have my bloggy posts gone?

Poor neglected blog. And what excuse have I? Too busy out conquering the world? Ministering to the needy? Hardly. Unless you count three growing boys with bottomless tummies. A little reading, a little research, a little homeschooling, a little housekeeping, a lot of planning. But I'll have to share that in another post.

First, we have our Eggshell Geodes to record! This is not an experiment for those who need immediate gratification. But if you're looking for a lesson to teach patience, it's perfect.

The idea is to make saturated solutions out of different solids -- we used salt, borax, and sugar. Then pour them into eggshells and let the water evaporate out the solutions. The process leaves crystallized solids in the eggshells -- similar to how mineralized water seeps into the air pockets of rocks to create geodes. (I suppose it takes longer than two weeks for a real geode to form, so I probably shouldn't complain. ;)

You might want to break this project into steps over a couple of days. We did it in one afternoon, and it took two hours to dissolve the three solutions one at a time, and pour into the eggshells. In retrospect, I might let each boy do one solution, and then share them! See Science Bob's site for more instructions.


Lessons learned (at least by Mommy)...
1) Peeling the membrane out of eggshells is not as easy as it sounds.
2) Epsom salts take a long time to dissolve.

(Littlest actually had the longest attention span for this one. Must have been the pouring and stirring!)


3) If you don't want purple blotches on your wood table, remember to put down the plastic tablecloth before starting an experiment. (We also had an accident with white-out that day. Who knew handwriting was more dangerous than chemistry?)
4) Don't leave the food coloring bottles in reach of the three-year-old when you're not watching.


I explained about solutions and saturation points, but I can't guarantee they were listening. That may have been the moment someone got into the food coloring without asking...



5) Sugar solutions take a loooong time to evaporate.
Two weeks later...


It worked! The crystals are not quite as dramatic in person unless you're holding them up to your nose, but each solid created a distinct form.

Did I ever show you this awesome apron my friend Becky made me? Isn't it the coolest?! She rocks. (No pun intended.)


This experiment serendipitously marks the end of our spring egg and bird study, and the beginning of a foray into the world of rocks and minerals.

Middlest has always loved rocks. My great-grandfather was a gemologist, so he must have gotten that gene! (He also got a huge collection of stones and petrified wood from my grandmother.) Last week we heard about a local geology club for kids, and all three boys wanted to join. We attended the first meeting, they used a grinder for the first time, and they got to take home a rock they polished themselves.

This summer we're going to see all kinds of incredible rock formations when we visit Yellowstone National Park, Bryce Canyon, and the Grand Canyon! More about that to come...

3 comments:

sarah in the woods said...

We did this too. Some of them worked great, like the sea salt, but I had a little trouble with the patience part and gave up on some of the other ones. Looking forward to hearing about your rock study.

Christina said...

Amanda, Amanda, Amanda-do you see me jumping up and down??!! Guess what we found on our way back from Sac. Lots of caves that we can visit. There are three or four within 5 hour drive one way. Wanta come play with us (: Great rocks and minerals playing!

Daisy said...

Sounds like the BEST experiment! What a fun teacher you are!

I have that AAS book ready if you still want it. Just email me. (I neglected to save your email in my saved folder. UUGH).

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