mineral

Magnetite (Iron Ore)

Magnetite (Fe3O4)

Hardness: 5.5-6.5; Color: Iron-black to brownish-black; Luster: Metallic to sub-metallic; Crystal Structure: Isometric (octahedral); Cleavage: None; Specific Gravity: 5.1-5.2

Hardness: 5
Color: Iron-black to brownish-black
Luster: Metallic to sub-metallic

Identified May 19, 2026More mineral →

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Physical properties

Hardness: 5.5-6.5; Color: Iron-black to brownish-black; Luster: Metallic to sub-metallic; Crystal Structure: Isometric (octahedral); Cleavage: None; Specific Gravity: 5.1-5.2

Formation & geological history

Formed in igneous, metamorphic, and sedimentary environments. Often found as an accessory mineral in igneous rocks like basalt and gabbro, or in banded iron formations through chemical precipitation.

Uses & applications

Primary ore of iron; used in heavy media separation, steel production, and as a pigment. Important in the gemstone trade when found as Lodestone for metaphysical collectors.

Geological facts

Magnetite is the most magnetic mineral on Earth. Naturally magnetized pieces are called Lodestones, which were used as early compasses by ancient mariners.

Field identification & locations

Identify using a magnet (it will be strongly attracted) and its black streak test. Commonly found in heavy sand deposits on beaches or in mountain plutons. Look for high density and metallic sheen.