When you dissolve the crystal powder in water, you’re creating a supersaturated solution which deposits extra molecules to form crystals. Just add water, mix, and wait a few days while your one-of-a-kind crystal grows to full size. To extend the life of your crystal, coat it with a layer of clear nail polish once it reaches full size. To reuse your crystals, simply allow all the water to evaporate and gently crush your crystals into a powder. Colors may vary. Crystals come in a 5.5" plastic test tube. About 27 g.