How to Make Black Crystals
- 1). Bend a black pipe cleaner into the desired shape for the crystal project. It's not absolutely necessary to use a black pipe cleaner; but any other color will stand out through any spaces between the crystals. The main consideration is that the pipe cleaner fit inside the wide mouth jar without touching the glass. Make sure the pipe cleaner design will also fit through the jar's mouth without becoming misshapen.
- 2). Cut a 5-inch strand of string. Tie one end to the top of the pipe cleaner design. Tie the other end around the center of a pencil. Place the pipe cleaner inside the jar with the pencil resting across the top of the jar. Check all sides to make sure the pipe cleaner dangles freely. Adjust the string length if necessary.
- 3). Remove the pencil/pipe cleaner. Fill the jar to within 1 inch of the rim with water. Pour the jar water into a measuring cup. This step is important, because it will tell you exactly how much water the jar holds so you will know how much borax to add.
- 4). Pour the water from the measuring cup into a saucepan. Heat the water until it boils.
- 5). Pour the boiling water into the jar. Add three tablespoons of 20 Mule Team Borax for each cup of water. Substitutes for 20 Mule Team Borax will not work. Crystals will only form in a highly concentrated solution. Stir the water until the Borax dissolves. Sediment on the bottom of the jar is not a problem.
- 6). Stir five to ten drops of black food coloring into the mixture. The more food coloring you add, the darker the black crystals will be.
- 7). Hang the pipe cleaner inside the jar. Ensure that the pipe cleaner is not touching any part of the jar. Place the jar in a location where it will not be disturbed overnight.
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