Makovickyite

Chemical formula: Cu<sub>1.12</sub>Ag<sub>0.81</sub>Pb<sup>2+</sup><sub>0.27</sub>Bi<sup>3+</sup><sub>5.35</sub>S<sup>2-</sup><sub>9</sub>

Makovickyite is a rare sulfosalt mineral of silver, copper, lead, and bismuth, forming microscopic, spindle-shaped crystals.

## Characteristics Makovickyite is a rare, complex sulfide (sulfosalt) with a metallic appearance. It occurs as very fine, spindle-shaped or acicular crystals, which rarely exceed fractions of a millimeter in length. It typically forms aggregates within the mass of other sulfides or ore minerals. Due to its size, its visual features are difficult to assess with the naked eye and require significant magnification. It has a steel-gray color and a metallic luster. ## Physical Properties Makovickyite crystals exhibit a metallic luster. The mineral is opaque. Due to the small size of the crystals, properties such as hardness or density are difficult to measure precisely and are based on calculated and comparative data. The density calculated from the chemical formula and unit cell parameters is approximately 6.92 g/cm³. ## Colors and Varieties Makovickyite is a mineral with a constant composition and a uniform, steel-gray color. No colorful varieties or trade names are distinguished for it. ## History and Name The mineral was first described in 1977 by J. Mumpre, B. Fojtik, and Z. Novák. The name "makovickyite" was given in honor of Emil Makovicky (born 1940), a professor of mineralogy and crystallography at the University of Copenhagen, in recognition of his contributions to the study of sulfosalts. It was approved by the International Mineralogical Association (IMA) under number IMA1976-035. The type locality, from which the first described samples originated, is Zlatá Baňa in Slovakia. ## Uses Makovickyite has no industrial application. As a very rare and microscopic mineral, it is solely an object of scientific interest and for specialized collectors of rare minerals and micromounts.

Properties

Luster
Metallic
Streak
Black
Density
6.92
Cleavage
Good on {001}
Transparency
Opaque
Crystal system
Orthorhombic

Diagnostic features

## Identification Identification of makovickyite is impossible without advanced analytical techniques. It requires the use of an electron microscope with an EDS analyzer or X-ray diffraction (XRD) analysis to confirm its chemical composition and crystal structure. In ore studies under a polarizing microscope in reflected light, makovickyite can be preliminarily recognized by its anisotropy and crystal habit, but definitive identification requires chemical confirmation. ## Distinguishing from Similar Minerals Visually (on a micro scale), it can be confused with many other bismuth sulfosalts, such as pavonite, benjaminite, aikinite, or gladite. All these minerals have a similar appearance, metallic luster, gray color, and often co-occur. Certain differentiation is possible only based on chemical analysis. ## Crystal Forms Makovickyite forms fine, spindle-shaped, acicular, or platy crystals, often grouped into radial or chaotic aggregates. Crystals are elongated along the crystallographic b-axis.

Geological environment

## Genesis Makovickyite is a hydrothermal mineral. It forms in medium- to high-temperature ore veins rich in bismuth, silver, copper, and lead. ## Mineral Associations This mineral often co-occurs with other sulfides and sulfosalts. The most common associated minerals include: bismuthinite, pavonite, aikinite, chalcopyrite, pyrite, quartz, as well as other, rarer bismuth sulfosalts. At the type locality (Zlatá Baňa), it was found in association with chalcopyrite, pyrite, tetrahedrite, native bismuth, bismuthinite, aikinite, gladite, emplectite, and pavonite. ## Localities Beyond the type locality in Zlatá Baňa, Slovakia, makovickyite has been identified in several other locations worldwide. Confirmed occurrences include, among others, the Baita Bihorului mine in Romania, quartz veins in the Kyzyl-Turan region in Russia (Tuva Republic), and the Kanimansur polymetallic deposit in Tajikistan.

Rarity

Very rare

For collectors

## Quality Criteria The quality of makovickyite specimens is assessed primarily based on the abundance and development of microscopic crystals. The most valued samples are those showing well-formed, isolated crystals or rich aggregates, clearly standing out from the background (matrix). Association with other rare minerals is also important. Since identification is only possible analytically, reliable labeling of the specimen, preferably with confirmation from a reputable laboratory, is crucial. ## Popular Localities The most classic and sought-after specimens by collectors come from the type locality - Zlatá Baňa in Slovakia. Samples from this location have historical and reference value.

Care and storage

## Cleaning Specimens containing makovickyite, typically micromounts, should not be cleaned mechanically or chemically. Dust can only be removed using a photographic air blower or compressed air from a safe distance. ## What to Avoid Avoid contact with any chemicals, acids, and detergents. The mineral is susceptible to oxidation, so it should be protected from moisture and sudden temperature changes. It should not be washed with water or cleaned with ultrasound. ## Storage Micromount specimens should be stored in dedicated, sealed boxes (so-called "micromount boxes") that protect them from dust, mechanical damage, and atmospheric factors. Store in a dry place with stable temperature.

Sources

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