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 a science, activity, it’s a nature craft, 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 use something other than pipe cleaners this time.
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
- spoon
- 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!
Your kids will also love:
Get my latest e-book: Fizz, Pop, Bang! Playful Science and Math Activities
40 hands-on, learning activities for kids ages 3-8. Recipes, experiments, art projects, printables and play ideas with links to 80 activities not featured in the book.
Download your copy today for just 9.99
Follow the Hooligans on Facebook
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.
Kate Lloyd
Stunning.
Kate - The Craft Train
We’ll be making some of these! My daughter goes nuts for any form of rock/crystal activities and these look amazing
happyhooligans
Yay! I’m so glad you love the idea, Kate! Have fun making yours!
Carey
Veryyyy cool! Can they be sealed with a clear acrylic spray?
happyhooligans
I’m not sure. I *think* it would probably work, Carey.
Ange
Do the rocks have to be from the ocean beach (salt water) or can it be any rock/ stone you find?
happyhooligans
No, not salt water rocks at all, Ange. In fact, I’m in Ontario, Canada. All of our water here is fresh water. Any smooth, clean stone will do. 🙂
Jennifer
Can food coloring be used instead of watercolors? And does the color rub off onto hands and surfaces even after it is dried?
happyhooligans
Saw your question on my Fb page, Jennifer, and answered you there. 🙂
Angela
I have the same question but I cannot find your facebook post. Can you post the answer here?
happyhooligans
I imagine you can use food colouring, Angela. I don’t think the colour would come off on your hand when the crystals have dried. They don’t with the liquid watercolours, which are water-based, like food-colouring is.
Beverley M
I’ve got four rocks soaking in borax now. Love your photos, hoping ours turn out as well tomorrow! Thanks for the idea!
happyhooligans
Yay! Let me know how they turn out, Beverley!
Sheree Spraglin
Hi, I was warned that borax causes eye and skin irritation when mixing it to make goop or flubber. Have you heard of this?
happyhooligans
Hi Sheree! Borax is a natural mineral. Warnings on the box state that it’s a mild irritant. I would imagine if you got it in your eye, there would be irritation. Steve Spangler, stated his opinions on Borax in this You Tube video, which you may find helpful: https://www.youtube.com/watch?v=mpSJdLyqibs
Nicole
Hi! I made this yesterday with 30 rocks for a class art project and I didn’t get much crystals on the rocks themselves. The bottom of the glass however is full of crystals. Any idea what I did wrong? I wonder if I can do it again to the same rocks to get more cystals? Thanks!
Jackie Currie
I can’t say for sure what the problem was. I wonder if the crystals weren’t fully dissolved before you added the rocks. You can try again, but the existing crystals on the rocks may melt when you put them into the hot water again. You can re-heat the jar with the crystals in it, and re-use that water though.
Nicole
I was so wrong! In the jars, you can’t see the crystals! But once i took them all out and they dried. WOW! So gorgeous! They all were so unique and beautiful even though I did not have white beach stones. I used stones from home depot (Colorado has no beaches) and instead of watercolors I am going to have the children use silver sharpie to write something they are grateful for and give to a special person. I have photos but where can I send the photos? Thank you for this idea. It’s been so fun! What a beautiful idea!
Jade
Do these stay on the rocks or does it go away over time??
Jackie Currie
They crystals stay on, Jade. We did find that the colouring faded over time, but the crystals are there to stay.
Kirsty
Do you have to use borax or do you think soda crystals work?
Jackie Currie
I don’t know what soda crystals are, Kirsty, so I really can’t say if they’ll work or not. I would do some googling to see if you can find any similar experiments that use them.
Alycia Diehl
I love this idea! If you tie a piece of fishing line or twine around your rock and suspend the rocks in your Borax solution you’ll get both sides and be able to Hang your masterpiece! The string gets coVered in crystals too! If you leave a tail dangling from the Urock and add beads to it or anything porous they will form crystals too. Your project is awesome and I just wanted to help with some variety for you and your hooligans
Hayley Turner
I tried this yesterday and it didn’t work. I did use plastic containers. Is that why?
Jackie Currie
It could be, Hayley. I’ve only every used glass jars for this experiment.
Catty
Waiting for borax to come in mail! Can’t wait to try it!
Jackie Currie
Yay! Have fun with them!