Black Tourmaline - Great value for all the tourmaline you will receive!!! Stones range in size 1/2"-1.5" in length and .25-1" in width Chakra: Earth, protects all Tourmaline comes from the Singhalese term "turamali", which translates as the stone of mixed colors. Tourmaline is often referred to as the rainbow gemstone. In Legend, Egyptians believed that tourmaline traveled from the earths' core to the surface along a rainbow which gave it all the various shades. Because these are natural, each stone will vary in size, shape and overall appearance. AVERAGE measure of stones is approximately 10-36mm x 20-40mm However each one varies in size.