Making borax crystals is a fun science experiment or STEM craft for curious kids. If your kid is crystal-obsessed like mine was when we made this project it’s even better!
We first published these borax crystals in 2014 when my oldest daughter was 5. It’s been updated and reshared for today’s audience.
Important: This is a science experiment that needs to be done under adult supervision only. Borax is definitely not safe to use around kids who are likely to try tasting or putting it in their mouth. It can usually be found in the cleaning aisle at the Supermarket or at Bunnings if you live in Australia, or you can order it on Amazon.
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The slime craze has taken over the world with such a frenzy that it’s easy to forget that borax has another fun use in kid’s science experiments. That is making crystals, of course.
You can make these crystal ornaments for Christmas decorating (they’d made great icicles!) or just for fun at any time of year like we did.
Making borax crystals is a perfect weekend science experiment for kids because it’s really easy, plus the crystals are fast growing so we did not have to wait a long time to see the results of our project.
Not surprisingly, this was a HUGE hit with my 5 year old, and she was pretty excited at the prospect of taking some of the crystal ornaments in to school for news after we made them.
How to make borax crystals
You will need:
- Borax (we used a whole tub and made lots of ornaments in different colours, but you need not do as many)
- Pipe Cleaners
- String
- Craft sticks
- Jars or glasses
- Food colouring (optional)
- Boiling water
How To:
Bend pipe cleaners into different shapes, then tie them with string to the craft sticks.
We learned by experience that it’s important not to make the shapes too large if you are using mason jars because the rim is narrower than the jar itself, and you need to be able to get the crystals out once they have grown. A couple of our jars needed to be smashed to get the crystal out without breaking it.
Fill each jar with boiling water from the kettle and stir in 1/3 cup of Borax until it has all dissolved (an adult must do this step). Add a few drops of food colouring if desired.
Tie the pipe cleaner shapes on to the craft sticks with string and hang over the jar so the pipe cleaner shape is completely immersed in the solution. We managed to fit two pipe cleaner shapes on to each craft stick.
Leave on the shelf for several hours or overnight, until the solution has completely cooled down and crystals have formed on the pipe cleaner.
We made our jars in the morning at around 11:00am and by 3:00pm the crystals had formed, to the girls great excitement.
Allow them to dry on paper towel, then you can hang them as ornaments.
So pretty!
Making Borax Crystals
Borax crystal science experiment for kids
Materials
- Borax
- Pipe Cleaners
- String
- Craft sticks
- Jars or glasses
- Food colouring (optional)
- Boiling water
Tools
- scissors
- measuring cup
Instructions
1) Bend pipe cleaners into different shapes, then tie them with string to the craft sticks. Make sure the shapes are small enough to pull out of the jar withour bending plus a small amount of space either side for the crystals to grow
2) Fill each jar with boiling water from the kettle and stir in 1/3 cup of Borax until it has all dissolved. Add a few drops of food colouring if desired.
3) Tie the pipe cleaner shapes on to the craft sticks with string and hang over the jar so the pipe cleaner shape is completely immersed in the solution. You can add two to a stick if there is space
4) Leave on the shelf for several hours or overnight, until the solution has completely cooled down and crystals have formed on the pipe cleaner.
5) Take the crystal ornaments out and allow to drain on paper towel before hanging
More STEM craft ideas for kids
Make an iphone speaker from a paper roll and cup
These mini lid banjos make a soft strumming sound
Make a straw swing set or see saw for the toys to play on
Create a solar oven from a cardboard box
Make a balloon-powered sponge boat for the bath tub or for outdoor play
Wow! THis looks great! Borax can be hard to find sometimes (we get it for our homemade laundry detergent!) but we will definitely give this one a go! 🙂 I think we’ll try it tomorrow in fact! Thanks for sharing – they look so great! I think our pipe cleaner shapes will resemble yours quite closely unless I get my thinking hat on!! 😉
We also Borax it for making detergent, which is why we had it in the cupboard 🙂 Hope the kids enjoy making them.
Thanks for this, I’ve been thinking of this experiment for a while but couldn’t remember how to do it exactly, planning to do it real soon with my son.
Its so interesting to watch!
Oh I love that you made these into a mobile! How gorgeous!
Your crystal ornaments look amazing…what a fun at home rainy day activity!
Wow they look so pretty 🙂
They are so pretty, I keep meaning to try this with my day care kids so thanks for the inspiration!! i already have some borax in the cupboard as i use it for washing powder too.
Are they durable or fragile?
Hi Denise, they are fairly fragile, more of an interesting experiment than a real crystal to keep forever. They are pretty much just pipe cleaner shapes with crumbly dried crystals all over them.
They’re really beautiful. Did they really form so quickly? That’s wonderful. I’ve wanted to make some too for a while but had heard that they take quite a while to form and so thought my kids might get a little impatient with them. They are really so lovely though.
I was surprised myself how quickly they formed. There are other types of crystals that take much longer to grow like salt and sugar crystals, but we have tried those too and the kids didn’t get impatient but they do like constantly going to check on the “experiment”.
How much liquid did you use with the 1/3 cup of borax? I tried the experiment with wide mouth quart jars, and we did not get crystallization. We are trying again today with a new solution with an extra 1/4 cup of borax.
We did not measure the amount of water, but just filled the jars tup to around 2/3 full, and they were mostly standard 500g pasta sauce jars. Hope it works this time for you. Try leaving the jars for longer if it doesn’t work. Ours formed very quickly but elsewhere I have read to leave the experiment for 24 hours
How did you clean it up afterwards? I did this for my chemistry class and now have crystallized beakers.
We did this a while ago but I think I threw the jars in the recycling, or the garbage for the ones we had to smash to remove the crystals from. They were just recycled food jars and I didn’t need to keep them. Would hot water clean your beakers and dissolve the crystals? I’ve not tried it. Sorry.
Will borax powder work? I’m unable to find borax crystals anywheree? Need reply ASAP!
The borax powder should work, it is the powder that turns into crystals
The ornaments look really cool! Just look at these crystals! I’d never think of using Borax for making crafts. I use it mainly as a cleaner and I think that actually is my favorite green cleaning substance in the house and I always have a box of Borax. Thanks for sharing this cool experiment. I love doing all kinds of crafts so I think that I will also enjoy making Borax crystal ornaments! 🙂 Greets!
Fantastic! I should use it more for cleaning too
Hi, can you plz tell me how to make sugar and salt crystals? Love the ones u made here! Can u maybe email me?
Not sure, probably in a similar way to this
We did this along with a lesson about the science of snowflakes. My sixth graders loved it. Some of my students decided they wanted to leave them over break to see if the crystals grew even bigger. I just don’t want them to degrade at all and leave them bummed. I will post what happens in case someone else wants to try this!
Wow, that sounds like it’s going to be interesting
Is there such a thing as leaving it in the borax for too long? What would happen if we left it for like a week?
You could always try it and see 🙂
Can i use persil gel instead of borax?
I’m not familiar with persil gel so I have no idea, but my guess is not
Can this be done using plastic cups? I really don’t want to risk tossing my glass jars.
I’m not sure, I have only tried this using jars
Hello
Do you please tell me how you make sugar and salt crystals? Like the ones you made here! Can you email me?
I’ve never made the sugar or salt version before, but I’m sure you could find a tutorial on Pinterest
Hello, can you tell me how to make sugar and salt crystals? Love the people you made here! Can you email me We did this with a lesson on the science of ice flakes? My sixth graders liked it. Some of my students decided that they wanted to drop them off during the break to find out that the crystals had grown even larger.
I’ve never tried making sugar or salt crystals, sorry. I’m glad you found this tutorial helpful.