Magnetite from Payún Matrú volcano, Mendoza Province, Argentina

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A loose floater cluster of what were once magnetite crystals, these now replaced by bright micaceous lustrous hematite. There are no points of attachment and this is complete all around. In excellent condition. Collected around the year 2005. The Payun Matru Volcano, located in the Mendoza Province of Argentina, is a large shield volcano situated within the back-arc region of the Andean Volcanic Belt. Formed by the subduction of the Nazca Plate beneath the South American Plate, the volcano features a prominent summit caldera created by major explosive activity during the Late Pleistocene, alongside extensive basaltic and trachytic lava fields that include some of the longest Quaternary lava flows on Earth. Pseudomorphs occur when one mineral replaces another while preserving the original crystal form. At localities such as Payun Matru, hydrothermal and fumarolic activity can cause magnetite crystals to undergo oxidation, transforming into hematite while retaining their sharp, original octahedral geometry.