A mineral with rhombohedral crystals, KFe33+(SO4)2(OH)6.(noun)
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Use "jarosite" in a sentence
"Expedition leader Professor Groemer, who is based at the University of Innsbruck in Austria, explains: "We have a mineral here called jarosite - and that is exactly what we have on Mars.""
"Orange layers are colored by jarosite, an iron-rich sulfate mineral."
"From 176 to 180 feet, samples indicated limonite-jarosite and hematite in the matrix material and it is believed that this zone could also offer gold mineralization."