How to Make Color Crystals

Tie a piece of string or yarn to a butter knife. Set the knife on top of the mouth of the jar, with the string hanging inside of the jar. Make sure that the string doesn't touch the sides or bottom of the jar. Trim it so that it almost reaches the bottom. Remove the knife and string from the top of the jar.

Boil a cup of water and remove the pan from the heat.

Stir the sugar into the boiled water by teaspoonfuls. Stir the solution to dissolve the sugar following each addition. Stop adding sugar when it no longer dissolves when stirred but begins to accumulate on the bottom of the container.

Add food coloring a drop at a time until the solution deepens to the shade that you want your crystals to be.

Pour the sugar solution into the glass jar. Try not to get any undissolved sugar into the jar. Set the knife across the opening of the jar with the string dangling into the solution. Set the jar where it will be out of the way and undisturbed. Place a paper towel over the opening of the jar to keep dust out of it.

Check the crystals after 24 hours. You'll see them beginning to form on the string. Let the colored crystals keep growing for the next week, which is about when they'll stop growing on their own. Or you can remove them a little before that if they've grown as big as you want them to be.

Remove the string of crystals and hang them into a clean, dry jar to dry.