This beautiful wing-shaped, polished piece of quartz from Minas Gerais, Brazil, features “sprays” of black tourmaline (also called schorl) as well as opalized quartz (visible on the rear photo). Rainbows are evident in several areas. In Japan, drywall that incorporates black tourmaline is used to limit the effect of electronic interference. This piece weighs over 1 lb., 13 ounces and measures 7″ wide by 4″ high.