Oxyvanite

Chemical formula: V₃+₂V₄+O₅

Oxyvanite is a very rare vanadium oxide, forming microscopic, black crystals with a metallic luster, found in metamorphic rocks.

## Characteristics Oxyvanite is a vanadium oxide that occurs extremely rarely in nature. It forms very small, tabular or platy crystals, whose size rarely exceeds 0.1 mm. It is usually observed as fine, dispersed grains or small aggregates within the host rock. It is opaque and black in color. ## Physical Properties Oxyvanite crystals exhibit a strong, metallic luster. The mineral's hardness on the Mohs scale is approximately 7, making it relatively hard. Its density is high, with a measured value of 4.67 g/cm³. ## Colors and Varieties This mineral is uniform in color and occurs exclusively in black. No colored or commercial varieties are distinguished. ## History and Name The name "oxyvanite" directly refers to the mineral's chemical composition – it is an oxide (oxy-) of vanadium (-van-). It was first described in 1996 by D.M. Burt, M.F. Miller, E.E. Foord, J.E. Taggart Jr., and B.L. Hanson based on material from the Carlin mine in Nevada, USA. Approved by the International Mineralogical Association (IMA) in 1994 (IMA1994-041). ## Applications Due to its extreme rarity and microscopic crystal sizes, oxyvanite has no industrial applications. Its significance is purely scientific and collectible, although it is primarily sought after by specialized collectors of rare minerals.

Properties

Mohs hardness: 7
Luster: Metallic
Streak: Black
Density: 4.67
Cleavage: Perfect on {010}
Fracture: Uneven
Transparency: Opaque
Crystal system: Orthorhombic

Diagnostic features

## Identification Identification of oxyvanite is practically possible only through advanced laboratory methods, such as chemical analysis (EDS) and X-ray diffraction (XRD). Visually, under magnification, it can be recognized by its black color, metallic luster, and characteristic platy habit of crystals. It occurs in a specific geological environment. ## Distinguishing from Similar Minerals It can be confused with other black, metallic oxide minerals, such as hematite, magnetite, or ilmenite. Differentiation requires specialized chemical analysis confirming the dominance of vanadium. ## Crystal Forms Oxyvanite crystallizes as very small, thin, tabular or platy crystals, often forming small, radial aggregates or dispersed flakes on the rock surface.

Geological environment

## Genesis Oxyvanite forms under conditions of contact metamorphism. Its occurrence is associated with highly mineralized zones within carbonate-silicate rocks (limestones and mudstones) that have been subjected to high temperatures. It is a product of hydrothermal processes occurring in a vanadium-rich environment. ## Mineral Associations This mineral co-occurs with other vanadium minerals, such as karelianite, shcherbinaite, as well as with graphite, pyrite, quartz, barite, and various minerals from the mica group. ## Localities The only confirmed and described occurrence (type locality) of oxyvanite in the world is the Carlin gold mine in Eureka County, Nevada, USA.

Rarity

Extremely rare

For collectors

## Quality Criteria The collecting appeal of oxyvanite specimens primarily depends on the abundance and visibility of its microcrystals on the host rock. Samples with numerous, well-formed, lustrous crystals forming distinct aggregates are most valued. Contrast with a lighter host rock also enhances the visual appeal of the specimen. ## Popular Localities The only source of collectible specimens is the Carlin mine in Nevada, USA. Material from this locality is extremely difficult to acquire on the market.

Care and storage

## Cleaning Specimens containing oxyvanite, due to the microscopic size of the crystals and their embedding in the host rock, usually do not require cleaning. If necessary, compressed air can be used to remove dust. Contact with water and chemical agents should be avoided. ## What to Avoid Ultrasonic cleaners, as well as all acids and bases that could damage not only the oxyvanite itself but also associated minerals, should be avoided. The specimen should not be subjected to sudden temperature changes. ## Storage Specimens should be stored in stable conditions, in a dry place, away from direct sunlight. It is best to keep them in sealed "micromount" boxes to protect delicate crystals from mechanical damage and dust.

Sources

IMA Mineral List (CNMNC)