Bolotinaite

Chemical formula: (Na₇&#₉₇₄₄;)(Al₆Si₆O₂₄)F·₄H₂O

Bolotinaite is a very rare mineral from the sodalite group, distinguished by its unique chemical composition with fluorine and specific crystal structure.

## Characteristics Bolotinaite is a mineral from the sodalite group, occurring as small, colorless grains, usually less than 0.3 mm in size. Due to its size and mode of occurrence, it does not form macroscopic specimens, and its visual characteristics can only be assessed under magnification. It is transparent and exhibits a vitreous luster. ## Physical Properties This mineral is characterized by a Mohs hardness of 5. Its density is low, typical for tectosilicates. It does not exhibit cleavage, and its fracture is uneven. It is one of the few minerals from the sodalite group that contains fluorine as a dominant extra-framework component. ## Colors and Varieties Bolotinaite is colorless. No colored varieties are known. ## History and Name The mineral is named in honor of the Russian mineralogist and crystallochemist Irina Valerievna Bolotina from the Institute of Geological Problems, Kola Science Centre of the Russian Academy of Sciences in Apatity. It was approved as a new mineral species by the International Mineralogical Association (IMA) in 2022 (IMA2022-075). The discovery was made in material from the Khibiny alkaline complex on the Kola Peninsula, Russia. ## Applications Due to its extreme rarity and microscopic size, bolotinaite has no commercial or industrial applications. It is of purely scientific significance and is of interest to specialized micromineral collectors.

Properties

Mohs hardness: 5
Luster: Vitreous
Streak: White
Density: 2.33
Cleavage: None
Fracture: Uneven
Transparency: Transparent
Crystal system: Cubic

Diagnostic features

## Identification Identification of bolotinaite is possible only through advanced analytical methods, such as Raman spectroscopy, electron microprobe (EDS/WDS), and X-ray diffraction (XRD). Visual identification in the field or in a collection is impossible due to its microscopic size and lack of characteristic macroscopic features. ## Distinguishing from Similar Minerals Bolotinaite is practically indistinguishable visually from other colorless minerals of the sodalite group and feldspathoids occurring in the same environment, such as sodalite, natrolite, or analcime. It differs from them in chemical composition, particularly the dominant role of fluorine, which can only be confirmed analytically. ## Crystal Forms Bolotinaite occurs as anhedral (irregular) grains ranging from 50 to 300 micrometers in size, forming aggregates. No well-formed crystal habits have been observed.

Geological environment

## Genesis Bolotinaite forms in the late, low-temperature stages of hydrothermal processes within highly differentiated alkaline massifs. It crystallizes in voids and fractures in nepheline-sodalite pegmatites that cut foyaite (a variety of nephelinite). ## Mineral Associations This mineral co-occurs with other rare alkaline minerals. At the type locality (Oleniy Ruchey mine), it was found in association with eudialyte, lorenzenite, lamprophyllite, aegirine, microcline, nepheline, sodalite, and also with other minerals from the sodalite group, such as vladimirivanovite. ## Localities The only confirmed occurrence of bolotinaite in the world is its type locality: the Oleniy Ruchey mine in the Khibiny Massif on the Kola Peninsula, Murmansk Oblast, Russia.

Rarity

Extremely rare

For collectors

## Quality Criteria As a micromineral, the collector value of bolotinaite does not depend on traditional criteria such as size or color. The most valuable specimens are those where bolotinaite grains are clearly visible, well-isolated, and, most importantly, unequivocally identified analytically. A rich association with other rare minerals from this locality is key. ## Popular Localities The only source of specimens is the Oleniy Ruchey mine in the Khibiny Massif (Russia), which is known for supplying many unique and rare alkaline minerals.

Care and storage

## Cleaning Micromineral specimens, such as bolotinaite, generally do not require cleaning. If necessary, compressed air (from a safe distance) can be used to remove dust. Avoid contact with water and chemicals. ## What to Avoid Avoid all wet cleaning methods, ultrasonics, and contact with acids and bases. The mineral is sensitive to changes in temperature and humidity. Do not heat it. ## Storage The best way to store it is in a specialized micromount box, which protects the delicate specimen from dust, mechanical damage, and humidity changes. Store under stable room conditions.

Sources

IMA Mineral List (CNMNC)