Watermelon Tourmaline
Similar to the quartz family, tourmalines come in a wide variety of colors and have been popular semi-precious gemstones. It is a composition of complex borosilicate with a hardness of 7 and a trigonal crystalline structure. It has got good piezoelectric properties. Watermelon tourmaline is a descriptive name given to a tourmaline that is red or pink inside and green outside. It is used to heal certain polarity imbalances