Heart Borax Crystals Kids Science Activity

Try this fun and easy Valentine’s Day-themed science activity! These heart borax crystals quickly grow in just a few hours. Kids will be amazed to see the chemical reaction caused by mixing borax and water, which creates sparkling crystals.

Heart Borax Crystals Supplies

To make heart shaped borax crystals, first gather the supplies. You will need the following materials.

• colored pipe cleaners
• pot of boiling water
• 20 Mule Team powdered borax
• small sticks or skewers
• clean jars
• string
• scissors

The basic project idea is to create a pipe cleaner heart, which is suspended in a water and borax mixture in a jar. Crystals will form on the pipe cleaner within a few hours, and continue to grow if left overnight. Borax crystals are clear, hard and shimmery. The pipe cleaner color shows through the clear crystals.

How to Make Heart Crystals

Create heart shapes for the borax crystals to grow on, by shaping colored pipe cleaners. Cut a full length pipe cleaner in half. Twist the ends of a half together to create a small circle. Use your fingers to form the pipe cleaner circle into a heart.

Once you have created some pipe cleaner hearts, tie a short string onto each heart. Tie the other end of the string to a stick, wooden skewer, or pencil. The sticks must be long enough to rest on the top of the jar and suspend the hearts in the liquid. The hearts should hang in the middle of the jar, without touching the bottom.

Next, prepare the borax liquid. Bring a pot of water to a boil. Mix in 4 tbsp. of powered borax for every 1 cup of water. Stir until fully dissolved.

Finally, it’s time to begin the chemical reaction magic! Fill each jar with a suspended pipe cleaner heart with enough borax water to fully cover the heart. The heart should not touch the bottom or show above the liquid. This will allow crystals to form on the entire shape of the pipe cleaner heart. Now all that’s left is to wait! Check your crystals every few hours to see the progress.

When you are ready to remove the heart from the liquid, take it out of the jar and pat it dry on a paper towel. Discard the rest of the borax liquid and wash out the jar with hot water.

Borax crystal hearts are colorful and shimmery, thanks to the bright pipe cleaner colors inside!

Find more creative activities for kids on our Kids Activities page!

Katie Wallace

Hi, I’m Katie! I live with my husband and 4 kids in Coeur d’Alene, Idaho. I love Jesus, coffee, creative projects, photography, and traveling. I’ve previously worked as a web designer, journalist, and barista. I hope you enjoy our creative projects and family adventures!