This project uses hot tap water, not boiling water, so it's safer for young crystal growers. Place the crystal solution in the refrigerator and get sparkly needle-like crystals within a few minutes to a few hours. It's that easy! 1/2 cup Epsom salt 1/2 cup hot tap water food coloring (optional) instructions here: http://chemistry.about.com/od/crystalrecipes/ht/cupofcrystals.htm
How To Grow Epsom Salt (Magnesium Sulfate) Crystals
How To Grow Epsom Salt (Magnesium Sulfate) Crystals: Epsom salt is magnesium sulfate. It's easy to grow Epsom salt crystals. The crystals typically resemble shards or spikes. Initially the crystals are clear, though they whiten over time.
Copper sulfate crystals are among the easiest and most beautiful crystals that you can grow. The brilliant blue crystals can be grown relatively quickly and can become quite large. Here's how you can grow copper sulfate crystals yourself.