Home >> Science & Nature >> Rocks & Minerals

How Can I Make Crystals Grow on Clay Pots?

Growing crystals is an activity that can teach children about the principles of evaporation and also how crystals form in nature. Making crystal gardens on porous objects like clay pots, sponges or porous rock is a way to grow a unique kind of garden that kids will love to show their friends.

Things You'll Need

Clay pots
4 tbsp. water
4 tbsp. salt
Disposable cup
Spoon
2 tbsp. ammonia
2 tbsp. laundry bluing
Food coloring (optional)
Tray

Instructions

- 1
  Soak clay pots in water until the water is absorbed into the pots.
- 2
  Mix 4 tbsp. of water with 2 tbsp. of salt in a disposable cup. Stir to dissolve the salt. Add 2 tbsp. of ammonia and 2 tbsp. of laundry bluing and then stir until all ingredients are mixed together. At this point, if you want your crystals to be colored, add a few drops of the desired food coloring; otherwise, white crystals will form.
- 3
  Place the clay pots on the tray and pour the mixture all over them. Pour any undissolved salt on the pots as well, coating them completely in the mixture.
- 4
  Sit the tray in a covered outdoor area or a well-ventilated area overnight. By morning, crystals will have started to form. To "feed" the crystals and keep them growing, put 2 more tablespoons of salt in the leftover liquid in the bottom of the tray on the second day. On subsequent days, make half quantities of the crystal mixture and place it in the bottom of the tray.

Rocks & Minerals