Manganokhomyakovite
Chemical formula: Na<sub>12</sub>Ca<sub>6</sub>Sr<sub>3</sub>Mn<sup>2+</sup><sub>3</sub>W<sup>6+</sup>Zr<sup>4+</sup><sub>3</sub>(Si<sub>25</sub>O<sub>73</sub>)(O,OH,H<sub>2</sub>O)<sub>3</sub>(Cl,OH)<sub>2</sub>
Manganokhomyakovite is a very rare, yellow mineral from the eudialyte group, distinguished by its complex chemical composition with tungsten and zirconium.
Properties
- Mohs hardness
- 5
- Luster
- Vitreous
- Streak
- White
- Density
- 3.11
- Cleavage
- None
- Fracture
- Conchoidal
- Transparency
- Transparent
- Crystal system
- Trigonal
Diagnostic features
## Identification Identification of manganokhomyakovite is based on its characteristic yellow color, vitreous luster, and occurrence as fine grains. The locality is crucial – this mineral comes exclusively from the Dara-i-Pioz massif. Definitive identification is only possible using advanced analytical techniques, such as X-ray microanalysis (EDS/WDS), which can confirm its unique chemical composition with the presence of manganese, zirconium, and tungsten. ## Distinguishing from Similar Minerals Manganokhomyakovite can be confused with other yellow minerals from the eudialyte group, such as khomyakovite or oneillite. Visual distinction is practically impossible, as the differences lie in the dominance of various elements in specific positions of the crystal structure. Chemical analysis is necessary. ## Crystal Forms This mineral forms anhedral (irregular) to subhedral (poorly formed) grains, usually less than 1 mm in size. Better-formed, short crystals with rhombohedral outlines, typical of the trigonal system, are rarely observed.
Geological environment
## Genesis Manganokhomyakovite forms under unique geochemical conditions, in highly alkaline (hyperagpaitic) syenite pegmatites. These rocks are extremely enriched in rare elements such as zirconium, niobium, tungsten, and strontium. ## Mineral Associations This mineral coexists with a rich assemblage of other rare minerals. Its typical associations include quartz, aegirine, microcline, pectolite, polylithionite, tadzhikite-(Ce), and dusmatovite. ## Localities The only confirmed locality of manganokhomyakovite in the world is its type locality – the Dara-i-Pioz glacier in the Alay Mountains, Tajikistan. This is one of the world's most famous sites for rare alkaline minerals.
Rarity
Extremely rare
For collectors
## Quality Criteria In the case of a micromineral like manganokhomyakovite, the value of a specimen is determined by several factors. The most important are the size and degree of crystal development – the larger and better-formed, the more valuable. The intensity and purity of the yellow color and the abundance of occurrence on the rock matrix are also important. An additional advantage is the association with other rare and well-formed minerals. ## Popular Localities All collectible specimens come from a single location in the world: the Dara-i-Pioz massif in Tajikistan. Material from this locality is highly prized by collectors specializing in rare mineral species and systematic minerals.
Care and storage
## Cleaning Manganokhomyakovite specimens are typically microminerals that rarely require cleaning. If necessary, compressed air can be used to remove dust or a very soft brush. Ultrasonic cleaners should be avoided, as they can damage or detach small crystals from the matrix. ## What to Avoid Avoid contact with strong acids and other aggressive chemicals. Although it is a stable mineral, it is not recommended to expose it to sudden temperature changes. ## Storage The best way to store it is in a specialized "micromount" box, which protects delicate crystals from dust, moisture, and mechanical damage. Avoid exposure to direct sunlight, although there is no evidence of fading.