mineral

Magnetite (Iron Ore)

Iron(II,III) oxide (Fe3O4)

AI-generated identification · may be incorrect

Hardness: 5.5-6.5; Color: Black to brownish-black; Luster: Metallic to submetallic; Crystal structure: Isometric/Octahedral; Specific Gravity: 5.1-5.2; Streak: Black

Hardness: 5
Color: Black to brownish-black
Luster: Metallic to submetallic

Identified July 4, 2026More mineral →

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Physical properties

Hardness: 5.5-6.5; Color: Black to brownish-black; Luster: Metallic to submetallic; Crystal structure: Isometric/Octahedral; Specific Gravity: 5.1-5.2; Streak: Black

Formation & geological history

Found in igneous, metamorphic, and sedimentary rocks. Formed through magmatic segregation, contact metamorphism, or as a heavy mineral sand in sedimentary deposits. It is one of the most abundant iron oxide minerals.

Uses & applications

Primary ore of iron used for steel production. Used in medical imaging (MRI), as a heavy media for coal washing, and as a pigment in paints/ceramics.

Geological facts

Naturally magnetized magnetite is known as 'lodestone,' which was used in ancient times as the first compasses. It is the most magnetic naturally occurring mineral on Earth.

Field identification & locations

Identify by its strong attraction to a magnet and its black streak. Often feels heavy for its size due to high specific gravity. Found globally, notably in Sweden, Brazil, and the USA (Mesabi Range).