Borax Crystal Snowflakes
Materials: ★★☆ Available in most school laboratories or specialist stores
Difficulty: ★★☆ Can be done by science teachers
Safety: ★★☆ Some safety precautions required to perform safely
Categories: Crystals, Water and Solubility
Alternative titles: Pipe Cleaner Crystal Snowflakes
Summary
Make snowflake ornaments from pipe cleaners by growing borax crystals from a hot, supersaturated solution. Compare color methods (colored pipe cleaners, food coloring, or post-painting with watercolors) and observe how crystals form and how color moves through the crystal structure.
Procedure
- Shape small six-armed snowflakes from pipe cleaners (about 1.5 stems per snowflake) and tie a loop of nylon thread to hang each one; ensure they fit inside your jars without touching sides or bottom.
- Heat water to near boiling and pour into wide-mouth, heat-safe jars. Stir in borax a spoonful at a time until no more dissolves and a little remains undissolved on the bottom (a sign of supersaturation).
- Optional: Add a few drops of food coloring to one jar for an in-solution color test.
- Suspend one snowflake in each jar from a pencil or chopstick so it hangs freely; optionally place a paper cover over the top with a slit for the thread.
- Leave undisturbed 12–24 hours. Note the solution clearing and crystals growing on the pipe cleaners and jar walls.
- Lift out the snowflakes, let drip, and air-dry on paper towels.
- Optional post-color method: Use watercolor paint to gently brush a dried white crystal snowflake. Watch color wick inward along tiny gaps toward the pipe cleaner core; let dry completely before handling.
Links
Borax Crystal Snowflake Experiment - The Dad Lab:
Grow Your Own Giant Crystal Snowflake - Martha Stewart:
📄 How to make the best Crystal Snowflakes - Go Science Kids: https://gosciencekids.com/index.html%3Fp=2814.html
📄 Crystal Snowflakes - Fizzics Education: https://www.fizzicseducation.com.au/150-science-experiments/kitchen-chemistry-experiments/crystal-snowflakes/?srsltid=AfmBOopzua0cpcM_i-piQwGPKianhe8vq0gBsdqkTQxAyZDOrO83WSoo
Variations
- Test crystal size vs temperature by starting with just-boiled water in one jar and slightly cooler hot water in another.
- Grow thicker crystals by leaving snowflakes in fresh hot solution for a second day.
- Compare salts safely used for crystal crafts (for example, epsom salt for needle-like crystals) and contrast shapes with borax.
- Add a simple measurement: weigh each snowflake before and after growth to estimate crystal mass gained.
Safety Precautions
- Adult supervision required when handling hot water; use heat-safe jars on a stable surface.
- Wear safety glasses; avoid splashes when stirring hot solutions.
- Borax is not edible and may irritate skin and eyes; avoid contact, do not inhale dust, and wash hands after the activity.
- Keep all solutions and finished crystals out of reach of toddlers and pets; label jars “Do Not Drink.”
- Dispose of small amounts by diluting with plenty of water down a sink connected to a sanitary sewer; follow local guidelines.
- Allow glass to cool before washing; dissolve any residual crystals with hot water rather than scraping.
Questions to Consider
- Why do crystals grow as the hot solution cools? (Solubility decreases with temperature, so excess solute leaves solution and deposits on surfaces.)
- What evidence tells you the solution was supersaturated? (Some borax would no longer dissolve, and rapid crystal growth occurred upon standing.)
- Which coloring method produced the most attractive result and why? (Post-painting with watercolors often gives vivid color that wicks through tiny gaps without clouding large crystal faces.)
- Why are the crystals largest on the fuzzy pipe cleaner rather than in open water? (The fibers provide many nucleation sites where crystals can start and grow.)
- Why might crystals become dull or powdery after months in storage? (Efflorescence; the salt loses water and the surface dehydrates, turning opaque.)