Nolanite

Chemical formula: V₃+₄Fe₃+O₇(OH)

Nolanite is a rare iron and vanadium oxide, forming small, hexagonal crystals with a metallic luster.

## Characteristics Nolanite is a rare mineral from the oxide group, consisting mainly of vanadium and iron. It forms small, tabular or platy crystals with a hexagonal outline, rarely exceeding a few millimeters in size. It usually occurs as scattered, individual crystals or small aggregates within the host rock. Its dark color and metallic luster make it easily noticeable against brighter associated minerals. ## Physical Properties This mineral is characterized by a hardness of 5-5.5 on the Mohs scale. It is opaque and has a strong, metallic luster. Its density is relatively high, approximately 4.86 g/cm³. ## Colors and Varieties Nolanite is typically black to dark brown in color. No distinct color varieties or commercial varieties are recognized. ## History and Name The name nolanite was given in honor of Thomas Brennan Nolan (1901–1992), an American geologist and director of the United States Geological Survey (USGS) from 1956–1965. The mineral was first described in 1957 based on samples from the Beaverlodge uranium mine in northern Saskatchewan, Canada. ## Uses Due to its rarity and small crystal size, nolanite has no industrial applications. It is solely an object of interest for collectors specializing in rare minerals and scientists studying uranium-vanadium deposits.

Properties

Mohs hardness: 5-5.5
Luster: Metallic
Streak: Blackish-brown
Density: 4.86
Cleavage: None
Fracture: Uneven
Transparency: Opaque
Crystal system: Hexagonal

Diagnostic features

## Identification Nolanite can be identified by its hexagonal, tabular crystals, black color, metallic luster, and blackish-brown streak. Its occurrence in association with uranium and vanadium minerals is also characteristic. ## Distinguishing from Similar Minerals It can be confused with hematite or ilmenite. It differs from hematite by a slightly darker streak (hematite has a cherry-red streak) and different crystal habit. It differs from ilmenite by crystal habit and often mineral association. Final confirmation requires advanced analytical methods, such as X-ray diffraction (XRD) or chemical analysis (EDS). ## Crystal Forms Nolanite crystals are usually thin, tabular, with a hexagonal outline. They occur as single, scattered flakes or form small, radial aggregates.

Geological environment

## Genesis Nolanite is a low-temperature hydrothermal mineral. It forms in calcite-dolomite veins cutting rocks rich in uranium and vanadium. Its crystallization occurs under reducing conditions, often in the presence of bituminous substances. ## Mineral Associations This mineral co-occurs with uraninite, pyrite, chalcopyrite, hematite, siderite, dolomite, calcite, quartz, and various minerals from the chlorite group. At its discovery site (Beaverlodge, Canada), it was found in association with pitchblende (uraninite) and hematite. ## Localities The most important and classic locality for nolanite is the Beaverlodge area in Saskatchewan, Canada. It is also found in the Rössing uranium mine in Namibia and in the Freedom No. 2 deposit in San Juan County, Utah, USA. Occurrences have also been reported in Germany (Ronnenberg) and Italy (Val Graveglia).

Rarity

Very rare

For collectors

## Quality Criteria Specimens with sharp, well-formed, hexagonal crystals, clearly contrasting with the host rock, are most valued by collectors. Rich aggregates of crystals are also highly prized. The luster and size of individual crystals (though rarely exceeding a few millimeters) also contribute to the specimen's appeal. ## Popular Localities Specimens from the type locality, the Beaverlodge area in Canada, hold particular value for systematic collectors. Good quality crystals also come from the Rössing mine in Namibia.

Care and storage

## Cleaning Nolanite specimens should be cleaned very carefully, using a soft brush to remove dust. Due to its fragility and often small crystal size, ultrasonic cleaners and strong water jets should be avoided. If liquid is necessary, distilled water is recommended. ## What to Avoid Avoid contact with acids and strong chemicals, which can damage the mineral's surface. Nolanite is stable, but it should be protected from impacts and scratching by harder minerals. ## Storage Nolanite specimens, especially those with well-formed crystals, are best stored in separate, padded collector boxes to prevent mechanical damage. Protect from dust and moisture.

Sources

IMA Mineral List (CNMNC)