Vorlanite

Chemical formula: CaU⁶⁺O₄

Worlanite is a rare uranium mineral, a natural, anhydrous calcium uranate, found in the oxidation zones of uranium deposits.

## Characteristics Worlanite is a very rare mineral from the uranate group, chemically defined as anhydrous calcium uranate (CaUO₄). It forms very small, tabular or platy crystals, usually not exceeding 0.2 mm in size. Most often, it occurs as aggregates or coatings on other uranium minerals. Its crystals have a characteristic, pale yellow to yellowish-orange color and a strong, vitreous luster. ## Physical Properties Due to its extreme rarity and small crystal size, many physical properties of worlanite have not been fully investigated. Hardness is estimated at approximately 4 on the Mohs scale. The mineral exhibits strong radioactivity, which is typical for uranium-bearing minerals. Under ultraviolet radiation (both shortwave and longwave), it shows strong, green fluorescence. ## Colors and Varieties Worlanite occurs in shades from pale yellow to yellowish-orange. No varieties have been distinguished. ## History and Name The mineral was named in honor of Charles Worlan (1920-2010), an American mineral collector from New Mexico, who first found its samples. It was approved as a new mineral species by the International Mineralogical Association (IMA) in 2014. The description was made by Anthony R. Kampf and collaborators based on material from the Blue Lizard mine in San Juan County, Utah, USA. ## Uses Worlanite has no industrial application. It is of purely scientific and collecting significance as a very rare uranium mineral.

Properties

Mohs hardness
4
Luster
Vitreous
Streak
Light yellow
Density
5.46
Cleavage
Perfect on {0001}
Fracture
Uneven
Transparency
Transparent to translucent
Crystal system
Isometric

Diagnostic features

## Identification Key diagnostic features of worlanite include its pale yellow to yellowish-orange color, very small, tabular crystals, strong green fluorescence under UV light, and high radioactivity. It occurs in paragenesis with other secondary uranium minerals. ## Distinguishing from Similar Minerals Worlanite can be confused with other yellow uranium minerals, such as uranophane, boltwoodite, or becquerelite. Distinguishing it requires advanced analytical methods, such as X-ray diffraction (XRD) or chemical analysis (EDS/WDS), as it is visually almost identical to synthetic CaUO₄ and very similar to other uranates. ## Crystal Forms Worlanite forms thin, tabular crystals with a hexagonal or octagonal outline, often with truncated corners. These crystals rarely exceed 0.2 mm and typically occur as rosette-like or radial aggregates, as well as thin coatings.

Geological environment

## Genesis Worlanite is a secondary uranium mineral that forms in the oxidation zone of uranium-vanadium deposits, typically in sandstone sediments. It forms as a result of weathering and alteration of primary uranium minerals, such as uraninite, under alkaline and oxidizing conditions. ## Mineral Associations This mineral co-occurs with other secondary uranium and vanadium minerals. At its type locality (Blue Lizard mine), it was found in association with gypsum, calcite, metarossite, pascoite, rossite, uraninite, and uranophane. ## Localities The only confirmed and described occurrence of worlanite in the world is its type locality: Blue Lizard mine, Red Canyon, White Canyon District, San Juan County, Utah, USA.

Rarity

Extremely rare

For collectors

## Quality Criteria As an extremely rare micromineral, any well-identified specimen of worlanite is valuable to specialized collectors. Highly prized are samples with clearly developed, even microscopic, crystals forming aesthetic aggregates on a contrasting matrix. A rich association with other rare uranium minerals is also important. ## Popular Localities The only source of worlanite specimens is the Blue Lizard mine in Utah, USA. All samples available on the collector's market originate from this single locality.

Care and storage

## Cleaning Worlanite specimens should generally not be cleaned mechanically or chemically due to their fragility and small size. If absolutely necessary, compressed air can be used to remove dust. Avoid contact with water. ## What to Avoid As a uranium mineral, worlanite is strongly radioactive. It is absolutely essential to avoid inhaling dust and direct skin contact. Washing hands after each contact is mandatory. It should not be stored in areas of permanent human presence (desks, bedrooms). It should be protected from acids and other chemicals. ## Storage Worlanite specimens must be stored in special, lead-lined or thick-walled plastic containers, clearly marked as radioactive material. They should be kept away from other radiation-sensitive minerals and light-sensitive materials.

External references

Sources

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