Barikaite

Chemical formula: Ag₁+₃Pb₂+₁₀(Sb₃+₈As₃+₁₁)S₂-₄₀

Barikait is an extremely rare lead, silver, antimony, and arsenic sulfosalt, occurring as metallic-gray, opaque grains.

## Characteristics Barikait is a complex sulfosalt of lead, silver, antimony, and arsenic. It forms anhedral, meaning irregularly shaped, grains up to 200 micrometers in size, often intergrown with other minerals. No well-formed crystals have been observed. Visually, it is a gray, metallic mineral, opaque even in the thinnest splinters. ## Physical Properties The mineral is characterized by a metallic luster and is opaque. Its density, calculated based on chemical composition and unit cell parameters, is 5.83 g/cm³. Hardness has not been determined. ## Colors and Varieties Barikait is steel-gray to dark gray. No color varieties or commercial forms are known. ## History and Name The mineral was approved by the International Mineralogical Association (IMA) in 2020 under number IMA2020-053. Its name comes from the "Barika" research project, under which geological studies were conducted in the area of its discovery. The type locality is the Kirki mines in Thrace, Greece. ## Applications Due to its extreme rarity, barikait has no 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: 5.83
Cleavage: None
Transparency: Opaque
Crystal system: Monoclinic

Diagnostic features

## Identification Identification of barikait based on visual characteristics is impossible. It is one of many gray, metallic sulfosalts that look identical without specialized equipment. Definitive identification requires advanced analytical methods, such as X-ray microanalysis (EDS/WDS) to determine the exact chemical composition. ## Distinguishing from Similar Minerals It can be confused with numerous other lead, arsenic, and antimony sulfosalts, such as galena, kirkiite, tsugaruite, or andorite, with which it often co-occurs. The differences between them are subtle and mainly concern the proportions of elements in the crystal structure, which is impossible to assess visually. ## Crystal Forms Barikait occurs exclusively as anhedral (irregular) grains, forming small aggregates or inclusions in other minerals, mainly in galena.

Geological environment

## Genesis Barikait forms in low-sulfur, epithermal polymetallic deposits. It is a product of crystallization from hydrothermal solutions rich in lead, antimony, arsenic, and silver. ## Mineral Associations This mineral occurs in association with galena, sphalerite, pyrite, as well as rarer sulfosalts such as kirkiite, andorite VI, and tsugaruite. ## Localities The only confirmed locality of barikait in the world is its type locality – the Kirki mines, in the Evros region, Thrace (Greece).

Rarity

Extremely rare

For collectors

## Quality Criteria As a microscopic mineral, the value of a specimen is primarily determined by the certainty of its identification, preferably confirmed by chemical analysis. Another criterion is the abundance of its occurrence on the sample – the more barikait grains, the better. Aesthetics are of secondary importance, although specimens with clearly visible inclusions in the host rock are more desirable. ## Popular Localities The only source of specimens is the Kirki mines in Greece. Material from this locality is extremely difficult to obtain and is almost exclusively acquired by research institutions and the most advanced collectors of rare mineral species.

Care and storage

## Cleaning Barikait specimens are typically microminerals that do not require cleaning. If necessary, a soft, dry brush can be used to remove dust. Avoid water, detergents, and ultrasonic cleaning. ## What to Avoid The mineral is potentially sensitive to acids and other chemicals. As a sulfide, it may undergo slow oxidation in a humid environment. Avoid sudden temperature changes and direct sunlight. ## Storage It is recommended to store specimens in a dry place, preferably in a tightly sealed "micromount" box, to protect them from dust, moisture, and mechanical damage. Due to the lead and arsenic content, it is advisable to wash hands after handling the mineral.

Sources

IMA Mineral List (CNMNC)