Aluminum pan or glass dish
Coal or charcoal cracked open
Spoon and bowl
4 Tablespoons salt
4 Tablespoons water
2 Tablespoons clear ammonia
4 Tablespoons laundry bluing
Plastic bottles of food coloring

Directions:

Place the cracked coal or charcoal in the pan or dish, rough side up Mix the salt, water, ammonia, and bluing together in a bowl, stirring well to dissolve as much of the salt a possible. Pour the mixture over the charcoal and add drops of food coloring in spots if colorful crystals are desired. Place the dish where it will not be bumped. Be sure to caution the children NOT to taste the mixture, as it may be quite harmful. In a few hours, the crystals will begin to grow and will continue to grow as the liquid evaporates from the pan. These crystals will more closely resemble sea coral then gems.

NOTE: For safety reasons very young children should only help crack the charcoal and mix the salt and water.