Things You'll Need
Instructions
Fill each cup with warm water; the water shouldn't be hot enough to scald but should be hot to the touch.
Stir some alum into each cup; keep adding alum until it stops dissolving and settles on the bottom of the cup. Your solution is supersaturated, perfect for making crystals.
Add a few drops of food coloring to make colored crystals. If you add no color, your crystals will be clear. You can make several crystals if you like, adding different colors to each one, or if doing this in a classroom, each student can choose a different color.
Bend and twist pipe cleaners into different shapes. You can make spirals, snowflakes, stars, diamonds, squares, squiggles or anything else you can think of. Just make sure your shape does not touch the bottom of the cup and has a small loop at the top.
Slide the loop of your pipe cleaner onto a skewer and lay the skewer across the mouth of a cup so the shape is completely submerged. Leave the pipe cleaners in the alum solution overnight.
Remove the pipe cleaners gently from the solution. Crystals of varying sizes and shapes should be forming on your pipe cleaner.