Giant crystal tree may be next piece of art approved for Denver International Airport
Denver City Council will have its first reading to approve a $3.5 million contract with an artist for a giant piece of ...
University of Manchester2y
Prehistoric Brits used rare rock crystals to mark burial sites, research finds
Evidence for the use of rock crystal - a rare type of perfectly transparent quartz which forms in large hexagonal gems - has occasionally ... into tools such as arrow heads or scrapers - instead, ...