Tre Croci, Vetralla, Vico volcanic complex (Vico Lake), Viterbo Province, Latium, Italy

Fe²⁺Fe³⁺₂O₄

Crystal System: cubic
Colour: greyish black or iron black
Lustre: metallic, sub-metallic
Habitus: octahedral, dodecahedral, or rarely cubic.
Hardness: 5½ - 6½
Fracture: irregular/uneven
Cleavage: none
Density: 5.2 g/cm³ 
Origin and geological occurrence: it is a common accessory mineral in igneous and metamorphic rocks. In some cases, magmatic segregation or contact metamorphism may produce economic deposits. It occurs in sedimentary rocks and in detrital deposits.

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Smorf link

Samples:

	4.10 Magnetite Metallic massive aggregate. #oxides
	4.11 Magnetite Octahedral crystals #oxides
	4.22 Magnetite Massive granular aggregate. #oxides, economic minerals