Badakhshanite-(Y)

Chemical formula: Y₂Mn₂+₄Al(Si₂B₇BeO₂₄)

Badakhshanite-(Y) is a rare mineral from the kanonaite-welinite group, distinguished by its complex chemical composition containing yttrium, beryllium, and boron.

## Characteristics Badakhshanite-(Y) is a very rare mineral with a complex structure and chemical composition, belonging to the kanonaite-welinite group. It forms small, granular aggregates or individual, poorly formed crystals, usually not exceeding 1 mm in size. Its appearance is inconspicuous, and identification requires advanced analytical methods. ## Physical Properties This mineral is characterized by a hardness of approximately 6 on the Mohs scale. It has a vitreous luster and is translucent. The calculated density is 4.15 g/cm³. It exhibits no cleavage, and its fracture is uneven. ## Colors and Varieties Observed specimens range in color from light brown to reddish-brown. Due to its extreme rarity, no varieties of this mineral have been distinguished. ## History and Name The mineral's name comes from its discovery locality in Badakhshan Province, Tajikistan. The -(Y) suffix in the name indicates the dominant rare-earth element in its composition – yttrium. It was officially approved as a new mineral by the International Mineralogical Association (IMA) in 2016 (IMA number 2016-088).

Properties

Mohs hardness: 6
Luster: Vitreous
Streak: Light brown
Density: 4.15
Cleavage: None
Fracture: Uneven
Transparency: Translucent
Crystal system: Trigonal

Diagnostic features

## Identification Accurate identification of badakhshanite-(Y) is impossible without advanced analytical techniques, such as electron spectroscopy (EDS/WDS) to determine chemical composition and X-ray diffraction (XRD) to confirm crystal structure. In field conditions and typical collections, it is unrecognizable. ## Distinguishing from similar minerals It can be confused with other rare minerals from the kanonaite-welinite group, such as welinite or manganwelinite, from which it is distinguished by the dominance of yttrium in its composition. Visually, it is indistinguishable from many other brown, granular minerals found in similar environments. ## Crystal forms This mineral forms anhedral (unformed) to subhedral (poorly formed) grains, which occur as aggregates or as individual inclusions in other minerals, mainly quartz.

Geological environment

## Genesis Badakhshanite-(Y) forms under hydrothermal conditions, in veins cutting metamorphic rocks. Its crystallization is associated with the presence of fluids rich in elements such as yttrium, beryllium, boron, and manganese. ## Mineral associations At the type locality (Darai-Pioz mine), it coexists with quartz, microcline, aegirine, polylithionite, leucophanite, reedmergnerite, and pekovite. ## Localities The only confirmed occurrence of this mineral in the world is its type locality – the Darai-Pioz Glacier in the Alay Mountains, Tajikistan. This is a famous mineralogical locality, known for the occurrence of many rare minerals.

Rarity

Extremely rare

For collectors

## Quality criteria The quality of a badakhshanite-(Y) specimen is determined primarily by its scientific value and confirmed identity. Collector value is secondary. The most valuable specimens are those in which the mineral grains are as large as possible, clearly visible, and well-documented analytically. The presence of associated minerals from the type locality can increase the attractiveness of the specimen for specialized collectors. ## Popular localities The only source of specimens is the Darai-Pioz Glacier in Tajikistan. Specimens from this locality are extremely difficult to obtain and appear on the market very rarely, mainly through specialized dealers or scientific institutions.

Care and storage

## Cleaning Due to the extreme rarity and small size of specimens, mechanical cleaning is not recommended. If absolutely necessary, compressed air can be used to remove loose dust. Avoid contact with water and chemicals. ## What to avoid Avoid all chemicals, acids, and ultrasonics. The mineral should be protected from high temperatures and sudden temperature changes. Due to the lack of data on its stability, it should be assumed to be sensitive to external factors. ## Storage Badakhshanite-(Y) specimens are typically microscopic and stored in specialized "micromount" boxes or embedded in resin. They should be kept in stable conditions, away from dust, moisture, and direct sunlight.

Sources

IMA Mineral List (CNMNC)