demonstrations:borax_crystal_snowflakes

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

  1. 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.
  2. 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).
  3. Optional: Add a few drops of food coloring to one jar for an in-solution color test.
  4. 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.
  5. Leave undisturbed 12–24 hours. Note the solution clearing and crystals growing on the pipe cleaners and jar walls.
  6. Lift out the snowflakes, let drip, and air-dry on paper towels.
  7. 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.

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.)