A red, yellow, or brown mineral, essentially HFeO2, one of the common constituents of rust.(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.
Use "goethite" in a sentence
"He was fascinated by minerals and early mineralogy (the mineral goethite is named for him)."
"The experiments, reported in the European journal Water Research, used a mineral called goethite, an iron-bearing oxide that is abundant on the ocean floor."
"Low goethite: Mineralogical studies of the bauxite suggest that abundances of the problematic iron hydroxide mineral species called goethite are very low to absent."