Beautifully colored in tones of deep violet midnight blue and white or reddish brown and white, the dumortierite gemstone is a favorite of the jeweler, the ayurvedic healer, the reiki practitioner and the magical practitioner alike. These gems are believed to sharpen the mind and are frequently used to improve memory and to enhance one's abilities in mathematics and language. In addition, the healing crystals boost confidence and assertiveness. When you purchase the Dumortierite Tumbled Gemstones for sale here at The Ancient Sage, you'll received a mixed assortment of colors and sizes of stones. The natural stones are sold by weight. 1/4 lb. package.