A Geoscience Digital Image Library

TitleTourmaline Schist
DescriptionTourmaline is actually a name for a group of similar minerals. They generally follow the chemical formula AX3Y6(BO3)3 Si6O18(O,OH,F)4. Tourmalines have some unique properties like they are piezoelectric which means that when a crystal is heated, compressed or vibrated a different electrical charge will form at opposite ends of the crystal (an electrical potential). Conversely if an electrical potential is applied to the crystal, it will vibrate. They are also pleochroic. This sample is about 14 cm.
LocationUSA ▹ South Dakota. Near Black Hills. Peerless Mine.
PhotographerShannon Heinle. 2001-11-27.
CollectionUniversity of North Dakota Mineralogy Collection #2310.
Key wordstourmaline, schist
Tech details968 KB. Hand specimen.
GeoDIL number1849