Grow sparkling, colourful crystals overnight from a safe solution of potassium aluminium sulfate. Single out the largest crystal shard, redissolve the remaining crystals, and repeat the crystal formation process to grow a larger, more striking crystal. This kit includes four packets of crystal-growing salt and two dyes (red and blue) so you can grow a variety of crystals in different sizes and colours. 

Recommended age: Ages 8+