An andalusite gem.
andalusite definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a very hard, orthorhombic silicate of aluminum, AlSiO, usually found in schist, slate, or other metamorphic rocks and used to make various high-temperature materials and as a gem
Origin: after Andalusia, where it was discovered
andalusite definition by American Heritage Dictionary
The American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
A mineral, aluminum silicate (Al2SiO5), usually found in orthorhombic crystals of various colors.
Origin: After Andalusia.
andalusite - Science Definition
A hard, grayish white to pinkish brown orthorhombic mineral. Andalusite occurs as nearly square prisms, often with cross-shaped cross sections, in metamorphic rocks. It is a polymorph of kyanite and sillimanite, but forms at shallower depths than they do, and at higher temperatures than kyanite and lower temperatures than sillimanite. Chemical formula: Al2SiO5.