The mineral form of black iron oxide, Fe3O4, that often occurs with magnesium, zinc, and manganese and is an important ore of iron.(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 "magnetite" in a sentence
"These mineral crystals were identified as magnetite, pyrrhotite, and greigite."
"In 1948, Néel made another fundamental discovery with his explanation of the strong magnetism found in the ferrite materials, of which magnetite is one."
"Like PAHs, these minerals -- mainly iron compounds called magnetite and pyrrhotite -- can come from inorganic sources."