Learn how crystals form different solutions as you grow your own set of aquamarine crystal clusters, moon crystal clusters and a crystal tree! Approximate size of crystal tree when completed: 2.75” diameter x 3.1”H. Ages 10 years + Buddies Tip? We sampled these and they were so cool! Make sure to find a safe warm spot to leave them. The growing time is different on each crystal, some were fast and some took a week!