How to make cute Borax crystal Christmas tree ornaments – fun Christmas science craft project for kids.
Do you remember our Borax crystal candy canes that we made last year? We decided to try a few more designs this year, and got a little carried away! I have a bunch of new crystal Christmas decorations to share, starting with these cute little crystal Christmas trees….
Suitable for
I’d recommend this activity for primary (elementary) school aged kids. Younger kids (5-6 year olds) could also give it a try, with assistance.
How to make cute crystal Christmas Tree Ornaments
You’ll need:
- Borax
- 12 ” 6mm green furry pipe cleaners (aka chenille stems)
- recycled glass jars (large enough that the trees can easily dangle inside)
- invisible nylon thread
- pegs (aka clothespins)
- safety glasses (optional, but recommended. We have these ones.)
What to do:
1. Fold the pipe cleaner in half. This middle point will become the top of your tree. Bend into a Christmas tree shape, with both ends twisting in the middle of the base of the tree. Cut off the ends.
2. Tie a loop of invisible nylon thread to the top of your tree. This will be used to hang the tree into the Borax suspension, and it will also be used later to hang your ornament on your tree. Twist the nylon thread loop onto a peg (or pencil), and check that the tree can easily dangle inside the jar.
3. Put on safety glasses. These next steps require adult supervision. (See safety notes below). Fill a glass jar with boiling water. (Careful – the glass will become very hot!) Add Borax powder to the water, and stir. The Borax will become suspended (ie, it will won’t settle on the bottom of the jar.)
The actual quantity of Borax required will depend on the volume of your jar – allow for about 3 tablespoons per 250ml of water. Or just keep adding and stirring until you’ve saturated the mixture and you start to see Borax collect on the bottom. (Note: Borax is not taste-safe.)
4. Lower the Christmas tree into the Borax suspension, balancing the peg on top. Double check that the tree isn’t touching the sides or bottom of the jar. Set aside in a safe place until the next day (or longer), with paper covering (optional, but it keeps out any bugs).
You should be able to see crystals forming by looking through the glass. Technically you should try not to disturb the jar, as this affects the crystals being formed. However neither daughters (nor I) could resist lifting the trees out of the suspension to check and recheck how the crystals were growing, so consider ours quite disturbed!
5. Once the crystals have stopped growing, remove from the jar, slide the nylon loop off the peg, rinse your crystal tree and let dry.
Now you have a new crystal Christmas tree ornament to study and hang (up high) on your tree!
Safety notes…
Be very careful with boiling water around young kids. Glass jars with boiling water inside will almost instantly become too hot to hold.
Borax is a commonly used natural ingredient in grade school science experiments, and is safe for older kids to handle when used responsibly. It is not edible however, and will irritate if put into eyes. It is also a mild skin irritant for people with sensitive skin. I recommend using safety glasses and washing hands afterwards.
With Borax being inedible, please make sure that your crystal creations are stored out of reach of babies, toddlers or pets (or hung high up, well out of reach, on your Christmas tree.)
All kids’ activities on this blog require attentive adult supervision. Parents and carers will need to judge whether a particular activity is appropriate their child’s age and skill level. Click here for more information.
I just love studying the crystals afterwards.
It is interesting to see how differently the crystals formed on the dark green vs the light green tree (with exactly the same process). The dark green pipe cleaner’s crystals are large and quite separate from each other, whereas the light green pipe cleaner’s crystals are smaller and tighter.
It just goes to show that every crystal formation is unique. And all are pretty!
Fun Science
Borax (also known as sodium borate, sodium tetraborate or disodium tetraborate) is a naturally occurring mineral and salt, that is mined from seasonal lakes. It is commonly used as a detergent alternative or laundry booster, and so you should be able to find it in the laundry aisle of your local grocery store (or you can also buy it online).
If you mix a small quantity of Borax with water, it will become suspended, which means that the water molecules can ‘hold’ onto it for a while, before eventually settling to the bottom of the jar.
If you heat up the water however, the water molecules move further apart, allowing more room for extra Borax to be suspended. As the water cools, the water molecules come closer together again, and can’t hold onto the same quantity of Borax as before. This is called supersaturation. The extra Borax separates from the water molecules and sticks to the pipe cleaners, forming beautiful crystals.
For more Christmas science ideas, check out our Christmas Science Projects & Experiments page, including:
- Borax crystal candy canes
- how to make a Christmas tree bubble wand (and learn bubble physics with play)
- and how to make a salt crystal tree decoration (a safer alternative for younger kids)
You might also like to check out our Go Science Kids and Fun Science for Kids boards on Pinterest.
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