• Ridgetop Farm and Garden

I have always wanted to make egg geodes with the kids. We finally did it!

It’s a fairly simple science project & can be done in a day or two. Most of that time is waiting for the crystals to form. We remade our mix 2 extra times, so it took us about a week to complete. With the exception of the alum, the supplies are items most people already have at home.

DAY 1: PREPARING THE EGGS

I carefully split open & washed 6 eggs.

Next, the kids spread regular ol’ school glue inside each of the egg shells.

Then they sprinkled alum on the wet glue. You want to cover the inside & top edge of your egg completely with alum. This alum gives the dissolved alum someplace to stick to when it cools & starts to form crystals.

I’m guessing the cheapest way to buy the alum is finding it in bulk online. But, I didn’t think that far ahead, so I just bought 4 small jars of McCormick’s alum at the super market.

The eggs dried overnight.

DAY 2

I put about 2.5 cups of water in a saucepan, then set it on the stovetop to heat the water. Right before it started boiling I dumped in 3 little jars of alum. After the alum dissolved I poured the mixture into 7 containers. Then, I added different colors of food coloring to each container. After the water cooled just a bit, I added an egg half to each cup. Then we let the eggs sit in their colored alum water for about a day and a half before checking them.

DAY 3

We took the eggs out of their colored alum water the next day. They were coming along well, but we stuck them back in their water to see if we would get even more crystals.

DAY 4

The next day, we checked the eggs again. They didn’t seem to have anymore crystals than the day before, so I took them all out of their water.

With the eggs sitting on the counter, I dumped the alum water in the saucepan. I also added a smidgen more water & alum.

The bottom of the containers had alum crystals, so those got scraped into the saucepan, too. I reheated the water, which dissolved the alum, then poured the water back into the containers. After cooling a little, I placed the eggs back in the containers for another overnight stay.

DAY 5

The next day we took the eggs out of the water for good. Most of the eggs did seem to have more crystals since their second alum bath.

COMPARISON

Egg Geodes Compare — After the first bath. After the second bath. The next day after it dried.

DAYS 6, 7, & 8

Because I couldn’t bare to waste what was left of the alum water. I mixed a couple of the colors together & repeated the process yet another time. This time we created crystals in 4 egg halves.

The eggs sat in the alum water for 2 days without being disturbed. I actually think I like the way these eggs turned out better than the first batch. There seemed to be a few more large crystals.

Making Egg Geodes