This science project allows students to explore mineral formation by creating stalactites and stalagmites using Epsom salt. Watch as crystals grow over time, illustrating geological processes in an accessible and hands-on way.
If Epsom salt is dissolved in water and allowed to evaporate, then stalactites and stalagmites will form as the crystals deposit.
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Dissolve 200 grams of Epsom salt in 500 mL of warm water.
Pour the solution into two clear plastic containers.
Suspend a piece of string from a stick laid across the top of one container, ensuring it's submerged.
Place a tea light candle underneath the second container to heat the solution.
Allow the containers to sit undisturbed for 1-2 weeks.
Observe the formation of crystals on the string and the bottom of the containers.
Measure the size of the stalactites and stalagmites formed.
Record daily observations of crystal growth.
Students should observe crystals forming on both the string and the bottom of the containers, demonstrating stalactite and stalagmite formation. The heated container may produce larger crystals more quickly than the cooler one.
Temperature of the solution
Size and rate of crystal growth
Amount of Epsom salt, Volume of water, Evaporation conditions
Handle hot water with care and avoid direct contact with the candle flame.
Create a visual timeline of crystal growth.
Use clear images of stalactites and stalagmites in your display.
Prepare a video of the experiment process.
Include a section on real-world applications of mineral formation.
Engage the audience with questions about geological processes.
Crystal formation can typically be observed after 1-2 weeks.
Yes, other salts could be tested, but results may vary.
Temperature, humidity, and the concentration of the solution can all impact crystal formation.
