How do I identify Vanarsite?

Vanarsite can be identified by its hardness of 2 on the Mohs scale, Very dark blue color. Look for these key characteristics when examining specimens.

What color is Vanarsite?

Vanarsite typically appears in Very dark blue. Color can vary depending on impurities and formation conditions.

How hard is Vanarsite?

Vanarsite has a hardness of 2 on the Mohs scale. This makes it a soft mineral that can be scratched easily.

Vanarsite

A variety of Minerals

What is Vanarsite?

Vanarsite, NaCa12(AsV3.5V8.5As6O51)2・78H2O, is a mineral that forms as very dark blue blades that are flattened on {100} and elongated on [010]. The crystals form in sub-parallel intergrowths in aggregates up to 5 mm long and are part of the cubic crystal system. The mineral is found in the Packrat mine in Colorado, USA in association with three mineral of similar composition, packratite, Ca11(AsV2V10As6O51)2・83H2O, morrisonite, Ca6(AsV2V10As6O51)2・78H2O, and gatewayite, Ca11(AsV3V9As6O51)・31H2O. Vanarsite has been determined to be part of the vanadate, arsenite, and arsenate groups. Analytical methods were used to determine its chemical composition, physical properties, and structure.

Vanarsite Market Value Calculator

Estimate the market value of Vanarsite using size, quality, and finish. This preview calculator is for quick context and is not a formal appraisal.

Vanarsite Localities Map

See where Vanarsite is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.

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North ZoneCentral RidgeSouth Basin

Key Characteristics

Formation of Vanarsite

Vanarsite is a relatively rare mineral with only a small quantity of the mineral having been found. It was discovered in the main tunnel of the Packrat mine, Gateway district, Mesa County, Colorado, USA. Packrat mine is located in the northern part of the Uravan Mineral Belt where uranium and vanadium containing minerals often occur together in sandstone from the Salt Wash member of the Jurassic Morrison Formation. Vanarsite was found located with three other minerals that were discovered at the same time in the same locality, packratite, morrisonite, and gatewayite and is also associated with pharmacolite. The mineral forms from the oxidation of montroseite and corvusite minerals in moist environments. Oxidized and unoxidized phases are exposed from mining operations. Ambient temperatures and oxidizing conditions near the surface cause water to react with pyrite and an unknown arsenic bearing phase to form aqueous solutions with low pH. Various secondary vanadate phases form depending on Eh-pH conditions and other cations present.