Daliranite

Chemical formula: Pb<sup>2+</sup>Hg<sup>2+</sup>As<sup>3+</sup><sub>2</sub>S<sup>2-</sup><sub>5</sub>

Daliranite is an extremely rare lead-mercury sulfosalt, forming acicular crystals with a metallic luster.

## Characteristics Daliranite is a sulfosalt of lead, mercury, and arsenic, occurring as very small, bladed or acicular crystals. It typically forms small, radial or disordered aggregates. Its crystals do not exceed several hundred micrometers in length. The mineral is opaque and has a characteristic, strong metallic luster. ## Physical Properties The luster of daliranite is metallic. The mineral is completely opaque. Its density, calculated based on chemical composition and unit cell parameters, is 5.55 g/cm³. Hardness on the Mohs scale has not been determined. ## Colors and Varieties This mineral has a consistent, characteristic color—from steel-gray to black. No color varieties or commercial varieties are known. ## History and Name Daliranite was first described in 2008. Its name honors Dr. Farahnaz Daliran, a German geologist of Iranian descent, for her contributions to the study of ore deposits in Iran, including the type locality of this mineral. ## Uses Due to its extreme rarity and microscopic size, daliranite has no commercial or industrial applications. It is solely an object of scientific interest and a valuable acquisition for specialized collectors of rare minerals.

Properties

Luster
Metallic
Streak
Black
Density
5.55
Cleavage
Perfect on {100}
Transparency
Opaque
Crystal system
Monoclinic

Diagnostic features

## Identification Identification of daliranite based on visual characteristics is impossible. Its recognition requires advanced analytical techniques, such as electron microprobe chemical analysis (EDS/WDS) and X-ray diffraction (XRD) to confirm the crystal structure. A characteristic feature is the co-occurrence of lead, mercury, and arsenic in its composition. ## Differentiation from Similar Minerals Daliranite can be confused with many other fine-grained, gray sulfosalts with a metallic luster, such as pierrotite, parapierrotite, or numerous other lead-arsenic sulfosalts. Definitive differentiation is only possible based on chemical analysis. ## Crystal Forms Daliranite forms elongated, bladed or acicular crystals, which often arrange into small, disordered or partially ordered, radial aggregates.

Geological environment

## Genesis Daliranite forms under low sulfidation conditions within epithermal systems. It has been found in highly silicified carbonate rocks, referred to as jasperoids. ## Mineral Associations This mineral co-occurs with other ore minerals, such as orpiment, realgar, cinnabar, stibnite, and pyrite. It is also accompanied by other rare sulfosalts, including pierrotite and parapierrotite. ## Localities The only confirmed occurrence of daliranite in the world is its type locality—the Zareh Shuran gold and arsenic deposit in West Azerbaijan Province, Iran.

Rarity

Extremely rare

For collectors

## Quality Criteria For such a rare micromineral, the collector's value is primarily determined by the richness of the specimen—the quantity and degree of development of daliranite crystal aggregates. An additional advantage is the association with other rare or well-formed accompanying minerals. ## Popular Localities The most highly valued, and indeed the only known specimens, come from the type locality in Zareh Shuran, Iran.

Care and storage

## Cleaning Daliranite specimens are extremely delicate and usually microscopic in size. Mechanical cleaning is highly risky and can destroy the specimen. Only very careful dust removal using a stream of compressed air from a safe distance is permissible. ## What to Avoid Avoid contact with water and all chemical agents. The mineral contains toxic elements (lead, mercury, arsenic), so avoid inhaling dust and direct skin contact. Wash hands after each contact with the specimen. Do not heat it or subject it to ultrasound. ## Storage It is recommended to store specimens in tightly sealed "micromount" containers to protect them from dust, moisture, and mechanical damage. The container should be clearly labeled as toxic material.

External references

Sources

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