tourmaline
Instance URI: http://resource.geosciml.org/classifier/cgi/commodity-code/tourmaline
Within scheme: South Australian Commodity Codes
Tourmaline is a crystal boron silicate mineral compounded with elements such as aluminium, iron, magnesium, sodium, lithium, or potassium. Tourmaline is classified as a semi-precious stone and the gemstone comes in a wide variety of colors.