With a small collection of simple ingredients stocked at your local grocery store, you can be making beautiful crystals in your own home in just a few days. Crystal making kits are available for purchase but why not try doing it yourself at home?
With a plaster mold, some alum (used for pickling and baking in the kitchen) and a few drops of food coloring you'll have fun creating a range of eye-catching and unique crystals. Follow these simple instructions to make your own.
TL;DR (Too Long; Didn't Read)
You can make attractive Amethyst colored crystals in your own home using commonly found ingredients, the process takes a few days makes for a fun and simple Science activity.
Creating a Geode
Mix plaster of Paris with water per the directions on the package.
Press the plaster into one section of the egg carton or other rounded object you have to use as a mold.
Let the plaster dry for about 30 minutes, then remove it from the egg carton to finish drying on its own.
Growing the Amethyst Crystals
Alum (Aluminium Sulfate) is a pickling spice and can be found in the cooking section of a grocery store. It is safe to pour down the drain, but not safe to eat.
Alum can irritate the skin and eyes and lead to health problems if inhaled so exercise caution and supervise children.
Keep your crystal safe from moisture and dust to preserve it
Stir alum into a half cup of water in any container. You should stir the alum until it stops dissolving which happens when the alum starts gathering at the bottom of the cup. At this point, you can add purple food coloring to give your crystals the color of an amethyst.
Place the geode you made from the plaster of Paris in a container that is big enough that your water mixture will just come over the top of your geode. Try not to allow any undissolved alum into the container.
Let the container sit undisturbed for two to three days while the crystals form. When you are satisfied with the size and appearance of your crystal, remove it from the container. Growing crystals is a subjective art you'll know when you are satisfied with the appearance of your crystals and as you experiment with different color shades and shapes you'll produce even more interesting samples.