Crystals come in all different shapes and sizes. However, the purest and cleanest crystals are usually also the ones that grow to be the largest in size. In this science fair project, you will compare the size and shape of crystals grown in three different temperature conditions: room temperature, in the refrigerator, and in an ice bath. With just water and borax, a household cleaning product, you can discover the best recrystallization method for growing large, pure crystals.