Tag: Borax

What’s the best way to make crystal snowflakes? Try this crafty winter science experiment for kids.

Make your own crystal snowflakes at home - Go Science Kids

Making crystal snowflakes seems to be the ‘classic’ Borax crystal science project. I’ve seen it in a bunch of places (like here, here, here, and here), but everyone seems to do it slightly differently. Some leave their snowflakes white. Some use coloured pipe cleaners. Some add food colouring to the solution. (And I’d heard of a fourth technique used to make crystal rocks, which I was super keen to try out with snowflakes to see if it worked!)

So, being a science family, we decided to do a little comparison experiment at home, to see which technique yielded the best looking crystal snowflakes.

Suitable for

Generally I’d recommend this activity for primary (elementary) aged kids (ie 7-9 year olds). Younger kids (5-6 year olds) may like to try it too, with assistance. My kids first made Borax crystals when they were 4 year olds, BUT they fully understood the need to take safety precautions and not put any Borax in their mouth. Please see safety notes at the bottom of this post when judging if this activity is right for your child.

Four ways to make crystal snowflakes

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We used:

  • 6mm furry pipe cleaners in white and navy blue (also called chenille stems)
  • invisible nylon thread and scissors
  • Borax powder
  • 4 wide mouth jars (or, more accurately,  we used 3 jars and 1 tumbler – as I didn’t have a 4th matching jar…)
  • boiling water
  • spoons for stirring
  • pencils or chopsticks for balancing on top
  • paper (optional)
  • safety glasses (optional, but recommended. We have these ones.)

Pipecleaner snowflakes - Go Science Kids

1. Create pipe cleaner snowflakes by cutting and twisting the pipe cleaners. We used about 1.5 pipe cleaners per snowflake. Please bear in mind that snowflakes are always six-sided. Your snowflakes also need to be small and narrow enough to be able to easy dangle inside your containers, without touching the sides or bottom. We made 3 x white and 1 x blue snowflake.

2. Tie on a loop of nylon thread to one of the snowflake arms of each snowflake. This will be used to dangle the snowflake inside the jar (and also doubles as a handy ornament hanger later on).

3. (Please see safety notes at the bottom of the post before starting this step.) Fill your jars with boiling water. Add Borax powder and stir. Keep adding Borax until the solution becomes super saturated and you can’t add any more without Borax powder settling on the bottom of the jar. We used about four tablespoons of Borax powder per jar.

4. Add blue food colouring to just one the jars.

5. Loop your snowflakes over pencils (or chopsticks), to balance on top of the jars. Add a white snowflake to the jar with the blue food colouring, and the other snowflakes to the remaining jars. You can also add paper covers if you wish, by cutting out a circle slightly larger than the jar diameter, and cutting a radial line for the thread to pass through.

Making Borax Crystal Snowflakes - Go Science Kids

6. Leave for 24 hours (or longer). The solution will be cloudy at first, but will start to clear after about an hour. You can start to see small crystals forming, and they’ll continue to grow for the next couple of days.

How to make Borax crystal snowflakes - Go Science Kid

7. Remove the snowflakes from the solutions. You should now have a blue crystal snowflake (the food colouring one), a second blue crystal snowflake (the blue pipe cleaner one), and two white snowflakes.

Crystal Snowflakes

8. Here’s where we tried out the special new technique! Use watercolour paints to paint one of the white crystal snowflakes blue, and watch how the crystals absorb the colour towards the centre of the structure – it’s fascinating! (Thanks Happy Hooligans for the inspiration!)

Watercolour Blue Crystal Snowflake

Below is a pic of the watercolour painted crystal after it’s had a chance to dry. Can you see how the large outer crystals have remained largely transparent, and that the blue colour has snuck in through the little crevasses, in towards the pipecleaner at the centre of the crystal structure? This is a great way to demonstrate how moisture can seep though rocks. SO AWESOME!

I’m so excited about this new technique – we’re definitely going to try this again!

Crystal painted with watercolour paints

But, ahem, getting back to our original question – what’s the best way to make crystal snowflakes?

Let’s compare.

Below is how they all look being held up to the window. (Top left = watercolour, top right = food colouring, bottom left = blue pipe cleaner, and bottom right = control / plain white.

Crystal snowflake collage

And here’s how they look outside in the sun. (The water colour one is the bottom right, and the food colouring one is bottom left.) I love how they all sparkle in the light!

Four crystal snowflakes in the sunshine

And here’s how they look on the coffee table inside. (You can tell the watercolour one by now right? It is at the top.)

Winter science craft for kids - how to make crystal snowflakes (experiment _ tutorial)

Crystal snowflakes - science craft for kids

The verdict?

For me, the watercolour snowflake wins, hands down. Not only are you able to choose the colour that you want more easily (as you can choose from the whole watercolour pallet), but the way the paint is absorbed through the crystal structure is both fascinating AND beautiful!

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. Borax has numerous industrial uses. It is often dissolved in water to form an alkaline antiseptic solution that is used as a disinfectant, detergent, and water softener (which is why you can often find it in the laundry aisle. Or you can also find it online).

When you stir Borax into very hot water, you can see that the water becomes very cloudy. This is because the Borax molecules become suspended in the water. As the water cools to room temperature, the solution becomes super saturated, and Borax separates from the water molecules and attaches to whatever it can, including the sides of the jar, and the pipe cleaner decoration dangling inside, forming beautiful translucent crystals.

Borax crystals are generally well formed and quite large, although you won’t typically find them in jewellery or in museum displays. This is because the crystals won’t hold their structure over long periods of time, like other crystals would. Because they are a salt, they go through a process called efflorescence. Dehydration causes the translucent crystals to become opaque, and eventually crumble into a white powder. (This is just starting to happen to the Borax crystal flowers we made almost 2 years ago, with a dusting of powdern just starting to appearing on the surface of the crystals).

Making crystal snowflakes would be a great winter science project, but as it happens, we made ours just before Christmas, and Christmas falls in summer-time in Australia! Snowflakes in summer? Ha! I guess somehow Christmas and snow are intrinsically linked, even for us down-under! (If you are interested, you can find more Christmas science projects here.)

Homemade crystal ornaments do look amazing hanging on your Christmas tree. (I have some pics of them on the tree, but they’re still on my camera. I’ll add them when I get a chance!)

We went a bit crystal crazy this year – it seems we’ve amassed quite a DIY Christmas crystal decorations collection! (And this pic below doesn’t even include the crystal candy canes that we made last year!)

DIY Crystal Christmas Decorations!

You can see all our crystal activities on Crystal Science page. Yes, we are officially crystal-obsessed. 🙂

While we are on the topic, just a quick note about storage. Because Borax is a salt, the crystals will eventually dehydrate, and start to crumble back into a white (or perhaps blue!) powder. This is a slow process – but it is starting to happen to some crystals we made about 2 years ago, and I’d like our Christmas crystals to last longer than that! So, in an attempt to slow down this process, I’m trialing storing our crystal Christmas ornaments in a zip lock bag between seasons to prevent moisture loss. I’ll let you know how they go!

Safety notes…

Be careful with boiling water around young kids. Place the glass jars down on a table before adding boiling water – glass with boiling water inside will quickly 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 directly into eyes. It is also a mild skin irritant for people with sensitive skin. Treat it like you would handing laundry powder. I recommend wearing safety glasses, using spoons, and washing hands afterwards.

With Borax being inedible, please be mindful of who might be able to reach your crystals afterwards. Make sure that your crystal creations are stored out of possible reach of babies, toddlers or pets. We hang ours up high on our Christmas tree, and store them in zip lock bags in our Christmas box in the garage for the rest of the year.

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.

Make your own DIY crystal snowflakes at home - Go Science Kids
You might also be interested in our Go Science Kids and Crystal Science boards on Pinterest.

And, of course, you can always subscribe to our newsletter, to receive all our latest activities straight in your Inbox. We’d love to have you join us!

* This post contains affiliate link(s) to similar products used. An affiliate link means I may earn a referral fee or commission if you make a purchase through my link, without any extra cost to you. Thank you for your support.

How to make a Borax crystal snowman ornament – cute winter or Christmas ‘science craft’ idea for kids.

Crystal Snowman Square

Yes, another crystal ornament post! My kids keep asking to make more, and I’m happy to oblige…

I know I’m mentioned this before, but I’ve found that repeating activities, with slight variations, is really worthwhile. If the kids are continuing to show an interest in something, that’s a sure sign there’s still more learning to be had!

So when my daughter Bumble Bee begged to make a crystal snowman, so she could hang one on our Christmas tree….

Make your own sparkly crystal snowman - fun crystal science craft for kids

Suitable for

Generally I’d recommend this activity for primary (elementary) aged kids (7-9 year olds). Younger kids (5-6 year olds) may like to try it too, with assistance.

You’ll see in the pictures below that I did this activity with my 4 year old daughter, BUT she had a lot of help from me. Bee’s also watched her big sister do this activity several times before, and so understood the steps involved and the need to follow instructions for safety.

How to make a Borax crystal snowman

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We used:

Ingredients to make crystal snowmen

What to do:

1. Twist a white pipe cleaner into two connected circles, making a snowman shape. Add a black pipe cleaner hat, trimming as necessary.

2. Tie a loop of invisible nylon thread to the middle of the snowman’s hat. (Nylon thread is tricky to tie for little hands. You can also use dental floss – which doesn’t look as good, but is much easier to tie on). Check that the snowman can easily dangle inside the glass without touching the bottom or sides.

Making a Borax crystal snowman

These next steps require adult supervision. (See safety notes below.)

3. Put on safety glasses. Fill a glass with boiling water. (Careful – the glass will become very hot!) Add Borax powder to the water, and stir. (Note: Borax is not taste-safe.)

Creating a Borax super-saturated solution

The actual quantity of Borax required will depend on the volume of your glass – allow for about 3-4 tablespoons per 250ml of water.

You’ll see the water become cloudy, but keep adding and stirring until it’s super-saturated and you can’t stir in any more without Borax powder collecting on the bottom.

Stirring Borax into hot water

4. Thread the nylon loop through a chopstick (or pencil) and lower the snowman into the Borax suspension, balancing the chopstick on top. Double check that it isn’t touching the sides or bottom off the glass. Set aside for 24 hours (or longer). Notice that the solution in the glass goes from cloudy, to relatively clear, to encrusted with crystals!

Three stages of making Borax crystal snowmen

5. When the crystals have stopped growing, remove the snowman from the glass, rinse and let dry. Now you have a new crystal snowman ornament to hang (up high) on your Christmas tree!

How to make a crystal snowman - fun chemistry for kids

I love studying the crystals afterwards. Every crystal formation is unique. So pretty!

Crystals

And they sparkle like crazy in the sunshine!

Borax crystal snowman

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. Borax has numerous industrial uses. It is often dissolved in water to form an alkaline antiseptic solution that is used as a disinfectant, detergent, and water softener (which is why you can often find it in the laundry aisle. Or you can also find it online).

When you stir Borax into very hot water, you can see that the water becomes very cloudy. This is because the Borax molecules become suspended in the water. As the water cools to room temperature, the solution becomes super saturated, and Borax separates from the water molecules and attaches to whatever it can, including the sides of the jar, and the pipe cleaner decoration dangling inside, forming beautiful translucent crystals.

Borax crystals are generally well formed and quite large, although you won’t typically find them in jewellery or in museum displays. This is because the crystals won’t hold their structure over long periods of time, like other crystals would. Because they are a salt, they go through a process called efflorescence. Dehydration causes the translucent crystals to become opaque, and eventually crumble into a white powder. (This is just starting to happen to the Borax crystal flowers we made almost 1.5 years ago, with a dusting of powder starting to appearing on the surface of the now opaque crystals).

How to make a crystal snowman ornament - cute science craft for kids

Safety notes…

Be careful with boiling water around young kids. Have kids place the glass on a surface before adding boiling water – glass with boiling water inside will become too hot to handle almost instantly.

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 directly 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.

Crystal snowman

For more DIY crystal ideas, we have a bunch listed on our Crystals page, including:

You might also be interested in our Go Science Kids and Crystal Science boards on Pinterest.

And, of course, you can always subscribe to our newsletter, to receive all our latest activities straight in your Inbox. We’d love to have you join us!

* This post contains affiliate link(s) to similar products used. An affiliate link means I may earn a referral fee or commission if you make a purchase through my link, without any extra cost to you. Thank you for your support.

How to make cute crystal holly ornaments – cute Christmas science craft project for kids.

How to make a crystal holly ornament - cute Christmas science craft for kids

 

Remember how I mentioned we have a bunch of new DIY crystal decorations to share for Christmas? This next one was a special request from my 4 year old – crystal holly!

 

 

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. This was too tricky for my 4 year old, but she watched with earnest, assisting where she could.

We made these in much the same way that we made our crystal Christmas trees earlier. I’ll repeat the main steps below.

 

 

How to make crystal Holly Christmas Ornaments

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You’ll need:

 

What to do:

1. Fold the green pipe cleaner in half. This middle point will become the tip of one of the holly leaves. Bend into a holly leaf shape, twist the two sides together at about the midway point, and the bend the remaining section into a second holly leaf shape, twisting the ends together to finish.

2. Twist the red pipe cleaner around the middle of your two holly leaves, and bend into several holly berry shapes.

Pipe cleaner holly

3. Tie a loop of invisible nylon thread to the end of one of your holly leaves. Thread this loop onto a chopstick (or pencil), and check that the holly can easily dangle inside the jar with the chopstick balancing on top.

4. These next steps require adult supervision. (See safety notes below). Put on safety glasses. Fill a glass jar with boiling water. (Careful – the glass jar will become very hot!) Add Borax powder to the water, and stir. (Note: Borax is not taste-safe.)

Stirring Borax

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.

 

5. Lower the holly into the Borax suspension, balancing the chopstick on top. Double check that the holly isn’t touching the jar. Set aside in a safe place until the next day (or longer).

Making crystal holly ornaments

 

6. When the crystals have stopped growing, remove the holly from the jar, slide the nylon loop off the chopstick, rinse your holly and let dry.

Now you have a new crystal holly ornament to hang (up high) on your Christmas tree!

DIY crystal holly ornament from Borax and pipe cleaners

 

 

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. Every crystal formation is unique. And all are pretty!

Studying the Borax crystals

Plus, they sparkle in the sunshine or under lights! It’s hard to capture in the photos – but believe me, it was glinting like crazy!

crystal holly ornamentsparkling DIY crystal holly ornament

 

 

 

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:

 

You might also be interested in our Go Science Kids and Crystal Science boards on Pinterest.

 

And, of course, you can always subscribe to our newsletter, to receive all our latest activities straight in your Inbox. We’d love to have you join us!

 

* This post contains affiliate link(s) to similar products used. An affiliate link means I may earn a referral fee or commission if you make a purchase through my link, without any extra cost to you. It helps to keep this little project afloat. Thank you so much for your support.

How to make cute Borax crystal Christmas tree ornaments – fun Christmas science craft project for kids.

DIY Crystal Christmas tree ornaments - Christmas STEM project for kids Science Craft

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….

Crystal tree ornaments

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

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You’ll need:

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.How to make pipe cleaner Christmas tree ornaments

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.)

Making Borax crystal Christmas trees

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!

Making Borax crystal Christmas trees - fun science for kids

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!

DIY Crystal Christmas tree ornaments - Christmas science project for kids Holiday STEM

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!Crystal Christmas tree decorations

Studying crystal formation Studying crystals

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.

How to make Borax crystal Christmas tree ornaments - fun Christmas science project for kids

For more Christmas science ideas, check out our Christmas Science Projects & Experiments page, including:

You might also like to check out our Go Science Kids and Fun Science for Kids boards on Pinterest.

And, of course, you can always subscribe to our newsletter, to receive all our latest activities straight in your Inbox. We’d love to have you join us!

* This post contains affiliate link(s) to similar products used. An affiliate link means I may earn a referral fee or commission if you make a purchase through my link, without any extra cost to you. It helps to keep this little project afloat. Thank you so much for your support.

How to make Borax crystal candy canes – fun Christmas science activity for kids.

How to make Crystal Candy Cane Ornaments - fun Christmas science project for kids

This article was first published on 5th August 2015, and has been since updated.

Jewel and I had so much fun making Borax crystal flowers earlier, that we thought we would try growing some more crystals and try out other designs. New crystal candy cane decorations for the Christmas tree sounded fun!

(I know, I know, but Christmas will be here before you know it!) Read More Crystal Candy Canes – fun Christmas science project

Make an interlocking crystal hearts necklace! Fun science & craft activity for kids.

Make an interlocking crystal hearts necklace - fun science for kids

Have you tried making crystals yet? They’re so pretty! This is our fourth ‘crystal craft’ we’ve made so far. We’ve also made crystal flowers, crystal candy canes, and a (preschooler-friendly) crystal snowy tree. This is our first interlocking-hearts design though!

Suitable for

Making Borax crystals is a classic science experiment for school aged kids. I’d recommend it for 5-6 year olds and up. (Jewel was almost 6 years old here). Older kids could experiment with a few different designs and materials, and see which works best.

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Two interlocking crystal hearts

How to make a Borax crystal hearts necklace

We used:

  • Borax (which you can buy at the grocery story in the laundry aisle, or online here)
  • pipe cleaners (also called chenille stems)
  • ribbon or fishing line (optional)
  • scissors
  • boiling water
  • spoons
  • glass jars
  • pencils
  • safety glasses (we have these ones)

To make our crystal hearts, the first step is to create the interlocking hearts shape. Cut a pipe cleaner in half. Bring the two ends of one half together and twist, making a loop. Thread the other half through the loop, and then bring those two ends together and twist making a second loop that goes through the first one. Pinch each loops to make two interlocked heart shapes.

Creating two joining hearts with pipecleaners

We made two sets of interlocking hearts – one for Jewel and one for me.

We decided to make ours into necklaces, so I tied a long piece of ribbon onto the end of mine. Jewel opted for blue pipe cleaners for her necklace. She twisting two pipe cleaners together to make an extra long one, and then twisting the ends of this around her hearts. (If you didn’t want to turn your hearts into a necklace, then I’d tie on something thin and slippery, like fishing line or floss, which the crystals won’t stick to and you can cut off later.)

The next step is to tie the ribbon / fishing wire / pipe cleaners to a pencil or chopstick, so the hearts can dangle below when your pencil is sitting on the rim of your glass jar. Measure it and check. (Don’t skip this step!) You need to make sure that your hearts dangle inside the glass jar, without touching the bottom or the sides. Make sure there’s a little bit of extra room too, as your hearts will become hard and slightly larger when they have crystals on them, and you want to make sure they don’t get stuck inside the jar. If in doubt, choose a larger container, or squish your hearts to make them smaller.

If you have safety glasses, put them on. It’s not strictly essential, but being safety concious around chemicals is a good habit. My girls love wearing their safety glasses whenever they get a chance – it makes it feel like a ‘real’ science activity! (If you don’t have any safety glasses, just make sure they don’t put any Borax in their eyes.)

With an adults help, fill your glass jars with boiling water. Add several tablespoons of Borax and stir until all the Borax is suspended (and looks dissolved). The actual quantity of Borax will depend on the volume of your jar – allow for about 3 tablespoons per 250ml of water.

(Please see safety notes at the bottom. Borax is not taste-safe. If you’ve happened to touch any of the Borax powder, please wash your hands. )

Adding Borax

Lower the hearts into the solution so that the pencil is sitting on top of the jar. Double check that your hearts aren’t touching the bottom or sides. Then place your jars in a safe spot where they won’t be disturbed.

Tie the hearts onto pencils and dangle into the Borax solution

Over the next 24 hours, your crystals will grow! You should be able to see some of the progress through the sides of the glass jar. It’s fascinating! The longer you leave them, the bigger they’ll grow, up to a point. We usually try to leave ours a few days.

Removing the crystal hearts from the Borax solution

Once the crystals have stopped growing (or your patience has run out), remove them from the solution and pat dry. You can rinse them off in fresh water if you want to. Untie your ribbon / pipe cleaner / fishing line, and admire your new crystal hearts!

Borax crystal hearts

There’s likely to be some crystals that have formed on the inside of the jar – these are pretty too!

Borax crystals formed inside the jar

Fun Science Fact

Borax (also known as sodium borate, sodium tetraborate or disodium tetraborate) is a naturally occurring mineral, that is mined from seasonal lakes. You don’t see it in crystal collections in museums though, because if it is allowed to fully dehydrate, it loses it’s structure and eventually crumbles into a white powder. Coincidentally it’s also, strangely enough, used as a detergent alternative and laundry booster, which is why you’ll likely be able to find it in your grocery store’s laundry aisle.

Water is made up of tiny molecules. If you mix Borax with water, some Borax can become ‘suspended’, which means that the water molecules can ‘hold’ onto it for a while. When water is very hot, the water molecules move further apart, and make room for the water molecules to ‘hold’ onto more of the Borax. As the water cools, the water molecules come closer together, and the water molecules can’t ‘hold’ the same quantity of Borax as they could before. This is called supersaturation. The extra Borax separates from the water molecules, and form crystals which stick to the pipe cleaners (and to the bottom of the jar).

Interconnected crystal hearts

The crystals formed are a mineral. They are hard. They are faceted. You can easily see their shape with your naked eye, but they are even more fascinating under a magnifying glass or a microscope.

Examining Borax cystals with a magnifying glass

Examining borax crystals

Your hearts will be ‘stuck’ together. If you’re game, you could try to break them apart, so the two crystal hearts are loosely entwined again. Some of the crystals may break off in this process though!

Joined crystal hearts

Two borax crystal hearts interlocked

Here’s Jewel, wearing her necklace. Doesn’t she look chuffed with her efforts!

Make your own interlocking crystal hearts necklace

Please note…

Be very careful with boiling water around young kids. Glass jars with boiling water inside will become too hot to touch.

Borax is a commonly used natural ingredient in grade school science experiments, and is safe for older kids to handle when used responsibly. However it is not edible, will irritate if put into eyes and is a mild skin irritant for people with sensitive skin.

With Borax being inedible, please make sure that your beautiful crystal hearts are stored out of reach of babies or toddlers.

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.

Interlocking crystal hearts - science and craft STEM or STEAM project for kids

For more heart-themed science craft ideas, you might also like our DIY heart-shaped bubble wands. (What shape bubbles will they make??)

And for more crystal ideas, you might also like:

We also have a pinterest board dedicated to growing crystals and crystal crafts!

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