Krasheninnikovite

Chemical formula: KNa<sub>2</sub>CaMg(S<sup>6+</sup>O<sub>4</sub>)<sub>3</sub>F

Krasheninnikovite is a rare potassium, sodium, calcium, and magnesium sulfate, forming tiny, hexagonal crystals in products of volcanic activity.

## Characteristics Krasheninnikovite is a mineral from the sulfate group, occurring as very small, hexagonal, prismatic or tabular crystals, usually not exceeding 0.2 mm. It forms aggregates, coatings, and crusts on basaltic lava in volcanic fumarole environments. The crystals are colorless to white and exhibit a vitreous luster. ## Physical Properties This mineral is relatively soft, with a hardness of about 2.5 on the Mohs scale. It is transparent to translucent. Due to the small size of the crystals, many of its physical properties, such as density or fracture, are difficult to measure precisely. ## Colors and Varieties Krasheninnikovite is typically colorless or white. No colored varieties have been distinguished. ## History and Name The mineral is named in honor of Stepan Petrovich Krasheninnikov (1711-1755), a Russian explorer, botanist, and geographer, researcher of Siberia and Kamchatka. It was approved as a new mineral by the IMA in 1998, and its description was published in 2000. The type locality is the fumaroles of Tolbachik volcano in Kamchatka. ## Uses Krasheninnikovite has no industrial application. Its significance is purely scientific and collectible, as a rare product of volcanic processes.

Properties

Mohs hardness
2.5
Luster
Vitreous
Streak
White
Density
2.83
Cleavage
Imperfect on {0001}
Fracture
Uneven
Transparency
Transparent to translucent
Crystal system
Hexagonal

Diagnostic features

## Identification Identification of krasheninnikovite is possible almost exclusively based on chemical analysis (EDS) and crystallographic analysis (XRD) due to its microscopic size and occurrence in complex parageneses. Visually, it is characterized by its occurrence as tiny, hexagonal, colorless crystals in fumarole products. ## Distinguishing from Similar Minerals It can be confused with many other sulfates occurring in the same environment, such as aphthitalite, langbeinite, or watsonite. Differentiation requires advanced analytical methods. Unlike some of them, krasheninnikovite contains fluorine. ## Crystal Forms It forms hexagonal crystals with prismatic or tabular habit. It occurs as single, dispersed microcrystals or forms thin crusts and coatings.

Geological environment

## Genesis Krasheninnikovite is a mineral of volcanic origin. It forms through sublimation from volcanic gases in active fumarole zones, crystallizing at high temperatures (above 600°C) on the surface of basaltic lava. ## Mineral Associations This mineral coexists with other sulfates and fluorides formed under similar conditions. It is most commonly associated with: aphthitalite, langbeinite, hematite, tenorite, halite, sylvite, as well as rarer minerals such as watsonite, arcanite, fluoborite, and sellaite. ## Localities The only confirmed and thoroughly described occurrences of krasheninnikovite in the world are located in the lava field of the second cone of the northern eruption of the Great Fissure of Tolbachik volcano in Kamchatka, Russia.

Rarity

Very rare

For collectors

## Quality Criteria The collector appeal of krasheninnikovite specimens depends on the abundance of microcrystals on the rock matrix and the presence of well-formed, though still microscopic, crystals. Due to its nature, it is a mineral primarily of interest to collectors specializing in systematic minerals, volcanic minerals, or "micromount" specimens. ## Popular Localities The only source of krasheninnikovite specimens is its type locality – Tolbachik volcano in Kamchatka. All specimens available on the collector's market originate from this single location.

Care and storage

## Cleaning Krasheninnikovite specimens are extremely delicate and sensitive to water. Mechanical cleaning is impossible due to the microscopic size and fragility of the crystals. Any contact with liquids should be avoided. ## What to Avoid The mineral is soluble in water. Contact with water, moisture, acids, and other chemicals must be strictly avoided. It should also be protected from high temperatures and mechanical shocks. ## Storage Specimens should be stored in tightly sealed "micromount" containers to protect them from atmospheric moisture and physical damage. It is best to keep them in a dry place with a stable temperature.

Sources

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