6 Tbls. Salt
6 Tbls. Liquid Bluing
6 Tbls. Water
1 Tbl. Ammonia
Combine salt, bluing, water and ammonia. Pour over small pieces of rock or coal in a shallow GLASS or CHINA bowl. Drip food coloring on top if desire. Crystals will begin to grow soon. Add water occasionally to keep crystals growing. You’ll probably want to place dish on tray or wooden board as crystals grow over the sides of the bowl.
From Anita, a teacher from Independence, IA