Amazonite
“The green feldspar mystery”
Amazonite is a green to blue-green variety of microcline feldspar whose color puzzled scientists for decades. Originally thought to be colored by copper, research has shown that trace amounts of lead and water in the crystal structure produce its distinctive blue-green hue.
potassium aluminum silicate (KAlSi₃O₈) with trace lead and water
Pikes Peak (Colorado, USA), Ilmensky Mountains (Russia), Kenticha (Ethiopia), Madagascar, Minas Gerais (Brazil)
6-6.5
Despite its name suggesting a connection to the Amazon River, amazonite has never actually been found in the Amazon basin — the name arose from confusion with green stones that indigenous peoples traded in the region.
Test Your Knowledge
What actually causes amazonite's green color?
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