Imagine you’re making an art project, with bead shapes in a pattern like this—round, diamond, triangle/round, diamond, triangle/round, diamond, triangle…In nature, crystals are minerals with shapes and patterns that repeat and repeat. 

Did you know you can grow crystals? Try this experiment using different crystal starters. See how many crystals you can grow in two weeks! (When your crystals are ready, you might even use them in a real art project.)

Print out a copy of the data sheet before you begin your experiment.

Label all the tall cups with material types. Measure 4 oz. of warm tap water into a measuring cup. Make sure you have an adult's supervision when getting warm tap water! (Add 1 teaspoon. of food coloring if you like—it helps make the crystals easier to see. You can use one color or a different color for each crystal starter.)

Add 1 tablespoon. of table salt to the warm water. Stir until the mixture looks as clear as possible. Add more salt by stirring in 1 tablespoon. at a time, until no more salt will dissolve and a little salt settles at the cup's bottom. Write down on your data sheet the number of tablespoons you added to the cup.

Take the tall cup labeled TABLE SALT. Fasten a pipe cleaner to the middle of a pencil, pen or stick. With a marker, mark the bottom 1 inch (2.54 cm) of the pipe cleaner (the part farthest from where the pipe cleaner is fastened). This is very important! Set the pencil, pen or stick across the top of the tall cup, as shown. Let the pipe cleaner hang down into the cup.

Pour the saltwater mixture into the tall cup. Make sure the cup is tall enough so that at least half the pipe cleaner is under water.

Repeat your experiment for each crystal starter you have. Make sure you use only 4 oz. of tap water and approximately the same water temperature each time. Remember to write all your data on the data sheet.

Set all the marked cups—each with its own pipe cleaner—in a place that gets lots of air (NOT inside a cabinet or refrigerator). Don't let anything touch or disturb the cups for 2 weeks.

After 14 days...Very carefully pull each pipe cleaner out of its cup, one pipe cleaner at a time. Do you see any geometric shapes such as short cubes, long cubes and double pyramids on the pipe cleaners? Do crystals on one pipe cleaner look like crystals on another pipe cleaner?

No crystals? Click here to find out why.

Examine the bottom 1 inch you marked on each pipe cleaner. Count all the crystals on that 1 inch of pipe cleaner only...

Crystal-Starter Ingredient Number of tablespoons dissolved in water Number of crystals on last inch of pipe cleaner
Table Salt
Epsom Salt