Learn how to make colourful crystallized beach rocks with Borax and liquid watercolours! This activity puts a spin on the classic Borax and pipe cleaner experiment, and it delivers gorgeous results.
I am SO excited to share our latest rock craft with you! It’s science, it’s art, and it’s totally, totally awesome!
Ok, you know that crystal experiment where you put a pipe cleaner into a jar of borax and hot water, and crystals form all over the pipe cleaner? If you’re not familiar with it, check out our icicle ornaments to see what I’m talking about.
We haven’t done that experiment in a couple of years, and I’ve been itching do it with the hooligans that I have this year, but I wanted to do it a little differently. I didn’t want to use pipe cleaners. I was brainstorming about what we could put into the borax and water solution when I spied a few smooth beach rocks on the kitchen windowsill. I’d set them there a few days ago, thinking we’d make paper weights with them. “Aha!” Maybe we could do the borax experiment with the rocks and make crystallized paperweights.
I really didn’t know if the borax experiment would work with rocks. Would the crystals actually form on a stone? I wasn’t sure, but I figured it was worth a try.
We experimented with one rock to see if it would work, and YAY, it did! The results were gorgeous! Overnight, our ordinary beach rock was transformed into a beautiful, white crystal, encrusted stone.
Then, I got thinking it would be cool to colour the crystal-covered rock. I had recently purchased these awesome liquid watercolours, (affiliate link) and I figured they’d be perfect to experiment with!
I whipped up more of the borax and water solution, and I crystallized several more rocks so each of the hooligans would have one or two to colour on our March Break Craft Camp day.
This is how our rocks looked after sitting overnight in the borax and water. Aren’t they amazing? They turned out so much better than I ever imagined they would!
Ok, ok! Let me show you how we made them!
For your convenience, this post contains affiliate links.
To make our crystallized beach rocks, we used:
- smooth beach rocks
- borax (in the UK, you can order Borax online here)
- hot water
- jars or plastic containers
- liquid watercolours
- medicine droppers or small paintbrushes
To crystallize our rocks:
First we filled a jar with 3 cups of very hot tap water. Then we added 9 tablespoons of borax. We stirred and stirred until the borax had dissolved. Then, using a spoon, we lowered our rock into the jar of borax-water, and left it on the counter to do its thing.
Crystals began to form on the rock and on the bottom of the jar within hours. To maximize the crystallization process, we left our rock in the borax solution overnight.
The next day, the crystals had kind of cemented the rock to the bottom of the jar, so we used a spoon to gently pry it loose. Take care to not force the rock free too quickly. You could chip some of the crystals off your stone.
We placed our stone on a paper towel to dry.
If you’re crystallizing a bunch of rocks like I did, pour your borax and water solution into several small containers or jars, and place one rock in each. I used small Gladware containers for the batch of rocks, making sure that each rock was completely submerged in the borax solution.
Now, to colour our crystals!
Adding colour to our crystallized beach rocks:
This part of the experiment was quick and easy, but WOW, was it ever impressive!
I poured a few drops of our liquid watercolours into an ice cube tray, and I added a couple of drops of water to each colour to dilute them a wee bit.
Then the hooligans used the droppers and paintbrushes to drip or brush the colour onto their rocks.
You should’ve heard the ooh’s and ahhh’s as the borax crystals soaked up the colour!
Most of the kids chose to colour their rock in one solid colour, dripping the colour on with the medicine droppers.
One child chose to use a couple of colours, and she painted them on in stripes with a paintbrush.
Aren’t the results incredible?
They look fantastic, don’t they? They’re so dazzling and vibrant!
I can’t tell you how excited we were with the way our rocks turned out.
What a fabulous project! Kids of all ages will love the process, but it’s easy enough that even toddlers and preschoolers can do it!
The hooligans now have these beautiful crystallized rocks to set on a dresser, or to use as a paperweight, or to wrap up, and give to a parent, grandparent or friend.
And now, it’s time for YOU to make some crystallized beach rocks of your own!
Drop me a line, and let me know how yours turned out! Or better yet, upload a photo to my Facebook page so I can see them!
If you enjoyed our crystallized beach rock activity, you’ll also like:
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Jackie is a mom, wife, home daycare provider, and the creative spirit behind Happy Hooligans. She specializes in kids’ crafts and activities, easy recipes, and parenting. She began blogging in 2011, and today, Happy Hooligans inspires more than 2 million parents, caregivers and Early Years Professionals all over the globe.