Roylco's Light Learning Rocks collection features 8 different nature-inspired shapes across 6 colors, produced in a beautiful transparent material to proomte color learning & sensory exploration. These gems have also been designed to function as tools for mindfulness and concentration building as their smooth curved edges and weight can create a calming effect. The set of 48 rocks includes a card deck of 36 pictures and patterns, sequences and stacking challenges that range in difficulty, Standalone or with a light table, these rocks bring magic into the classroom or home.