Definition of "sunstone" [sun•stone]

• See aventurine. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Such a tool, known as a sunstone, is known from legend, but until now experimental evidence that it could actually work as hypothesized was lacking."
• "In Dinotopia: The World Beneath, 1995, large caverns beneath the island are lit by glowing algae, "sunstone" crystals, and ferns."
• "For a "sunstone" they used a polarimeter, a device that measures polarization."