Caves are packed full of minerals. These mineral deposits form unique shapes that appear like icicles. They come in two forms stalactites which grow down from the ceiling. And stalagmites which grow up from the ground. In this cool science experiment we will grow our own Stalactites and Stalagmites.
Materials Needed To Make Stalactites:
Some Yarn or String
Four Metal washers
Four small glass jars or plastic cups
Process to Make Stalactites:
1) First measure out (6) two foot pieces of yarn or string and cut it off. Take (3) two foot pieces of yarn or string and braid them together. Tie a metal washer to the end of each side of the braided strings. Repeat braiding and washer process for remaining (3) pieces of string or yarn. The metal washers will serve as weights to keep the ends of the yarn or string in the glass jars.
2) Get some very warm or hot water (120-140 degrees) and fill one of the glass jars 2/3 of the way full. Start stirring in baking soda. The idea is to make a super saturated solution in which you keep stirring in baking soda until it will no longer dissolve. Dissolve in as much baking soda as you can! Do the same process with a second jar and more baking soda. Repeat the process with the two remaining jars and Epsom salt. You can add food coloring to your solution to form colorful cave formations.
3) Find a warm place and let the jars sit for a couple days. Next place one end of the braided string into a glass with baking soda solution and let the washer sit on the bottom. Put the other end of the braided string or yarn into the other glass of baking soda solution with washer at bottom (see image below). Repeat process with Epsom salt glasses, braided strings or yarn and washers. Arrange the cups so the strings hang down in a "U" shape. Place a plate under the "U" shape between the glasses.
4) Leave the glasses in a warm dry place for several days. You will start to see tiny Stalactites forming down from the string and tiny Stalagmites forming up from the plate.
The Science Behind Making Stalactites and Stalagmites:
Stalactites and Stalagmites are columns of stone that grow in caves. They form when mineral deposits dissolve in rainwater and then drip slowly from the roof and walls of underground caves. As the rainwater evaporates, it leaves only the mineral deposits (calcium carbonate) which forms these icicle like shapes. In our experiment we used baking soda and Epsom Salt as the dissolved minerals. As the mineral water soaked up onto our strings or yarn, dripped, and evaporated Stalactites and Stalagmites were formed! Now go grab some friends and make some cool cave formations.