Rutilo Epitaxial
Rutilo is a mineral with formula TiO₂, in the Óxidos group. This specimen comes from Rutilated Quartz Localities, Remedios, Novo Horizonte, Bahía, Brasil and joined the Terrium collection in 2026.
Description
Geometric epitaxial growth of rutile crystals with hematite. Good luster.
About Rutilo
The formation of these stars occurs in two phases. First, tabular hematite (Fe₂O₃) crystallizes, forming plates. Later, a new influx of hydrothermal fluids deposits rutile (TiO₂) onto their surfaces. Rutile does not grow at random: the crystal lattices of both minerals fit together best at specific angles. This is why the needles appear as distinct, straight, repeating, and geometric bundles.
About the locality
Minas Gerais is a region nearly the size of the Iberian Peninsula, industrialized to the point of depredation: heavy machinery, dynamite, and open-pit mining that have literally erased mountains from the map, leaving behind historic environmental disasters like Mariana and Brumadinho. Yet, it remains astonishingly generous to mineral collecting due to the sheer variety and exceptional quality of the species it has produced. It is a nearly unique case: typically, a mineralogical district is either highly diverse but unremarkable, or world-class but limited to just a few species. Minas Gerais defies that logic. It has «almost» everything.
Technical data
- Catalogue No.
- 0654
- Composition
- TiO₂
- Name
- Rutilo
- Variety
- Epitaxial
- Group
- Óxidos
- Matrix
- hematites
- Mine
- Rutilated Quartz Localities
- District / Municipality
- Remedios
- Province
- Novo Horizonte
- Region
- Bahía
- Country
- Brasil
- Size (cm)
- 3.2 x 2.8 x 0.4
- Weight
- 3.5 g
- Acquired
- 2026
- Etymology
- In Latin "rutilus" means reddish or shining.
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- Cianita — Brasil
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