Lavoisierite

Chemical formula: Mn²⁺₈[Al₁₀(Mn³⁺Mg)][Si₁₁P]O₄₄(OH)₁₂

Lavoisierite is a very rare silicate mineral, discovered in Spain, with a complex chemical composition containing manganese, aluminum, and phosphorus.

## Characteristics Lavoisierite is a mineral with an exceptionally complex chemical composition, belonging to the silicates. It occurs as very fine, platy crystals with a hexagonal outline, forming rosette-like or spherulitic aggregates. Individual crystals rarely exceed 20 micrometers in size, and entire aggregates reach up to 0.2 mm. The mineral is brittle and has an orange-brown color. ## Physical Properties Due to the microscopic size of the crystals, many physical properties, such as hardness or density, have not been precisely measured. The luster is described as vitreous. It is a translucent mineral. ## Colors and Varieties This mineral occurs in a uniform, orange-brown color. No varieties have been distinguished. ## History and Name Lavoisierite was approved as a new mineral by the International Mineralogical Association (IMA) in 2013 (IMA2013-080). Its name honors Antoine-Laurent de Lavoisier (1743–1794), an eminent French chemist, philosopher, and economist, recognized as the father of modern chemistry. He was honored for his fundamental contributions to understanding the chemical composition of substances, including oxides and water, and for his role in reforming chemical nomenclature. ## Applications Lavoisierite has no industrial applications. Its significance is purely scientific and collectible, as a unique and newly discovered mineral.

Properties

Color
Yellow-orange
Luster
Vitreous
Streak
White
Density
3.576
Cleavage
Perfect on {0001}
Transparency
Translucent
Crystal system
Orthorhombic

Diagnostic features

## Identification Identification of lavoisierite is impossible without advanced laboratory techniques, such as Raman spectroscopy, electron microprobe (EDS/WDS), and X-ray diffraction (XRD). In collector conditions, identification relies on a label from a confirmed locality. Visually, only orange-brown, microscopic, rosette-like aggregates on the matrix rock can be observed. ## Distinguishing from Similar Minerals Due to its unique chemical composition and structure, there are no minerals with which it could be directly confused after chemical analysis. Visually, it may resemble other microscopic silicates of similar color and habit, but certain differentiation is only possible through analytical methods. ## Crystal Forms Lavoisierite forms very small, thin, platy crystals with a hexagonal outline. These crystals combine into characteristic rosette-like or spherulitic (spherical) aggregates.

Geological environment

## Genesis Lavoisierite forms as a result of hydrothermal or low-grade metamorphic processes acting on manganese-rich sedimentary rocks. At its type locality (Fuente del Moro mine in Spain), it occurs in veins cutting radiolarites (siliceous rocks) mineralized with manganese oxides. ## Mineral Associations This mineral co-occurs with other manganese minerals and silicates. At the discovery site, it was found in association with quartz, alleghanyite, piemontite, rhodonite, tephroite, bementite, ganophyllite, aegirine, and manganese oxides. ## Localities The only confirmed occurrence of lavoisierite in the world is its type locality: Fuente del Moro mine, near Viñuela, in the province of Malaga, Andalusia (Spain).

Rarity

Extremely rare

For collectors

## Quality Criteria The quality of a lavoisierite specimen primarily depends on the abundance and visibility of microscopic aggregates on the matrix rock. The most prized samples are those where rosette-like clusters are numerous, well-formed, and contrast with the substrate. The size of the aggregates, although always microscopic, is also important – larger spherulites are more desirable. Analytical confirmation of the mineral's identity is crucial for its value. ## Popular Localities The only source of lavoisierite specimens is the Fuente del Moro mine in Spain, which is its type locality.

Care and storage

## Cleaning Lavoisierite specimens are extremely delicate and small, usually occurring as coatings on the matrix rock. Mechanical or chemical cleaning is not recommended. If necessary, compressed air (from a safe distance) can be used to remove dust. ## What to Avoid Avoid contact with any chemicals, acids, and detergents. Do not subject it to ultrasonic cleaning. Protect from high temperatures and sudden temperature changes. Due to its microscopic nature, avoid any touching or abrading of the specimen's surface. ## Storage Specimens should be stored in stable conditions, in sealed "micromount" containers, to protect them from dust, moisture, and mechanical damage. There are no special requirements regarding light exposure.

External references

Sources

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