Malyshevite
Chemical formula: Cu<sup>1+</sup>Pd<sup>2+</sup>Bi<sup>3+</sup>S<sup>2-</sup><sub>3</sub>
Malyshevit is an extremely rare copper, palladium, and bismuth sulfide, found exclusively as microscopic grains in Cu-Ni ores.
Description
## Characteristics Malyshevit is a sulfide with a complex chemical composition, containing copper, palladium, and bismuth. It occurs as very small, anhedral (irregularly shaped) grains, rarely exceeding 0.2 mm in size. It is usually strongly intergrown with other ore minerals. It is opaque and has a metallic luster, and its color is described as grayish-white with a slight, creamy tint. ## Physical Properties This mineral is characterized by a metallic luster and is opaque. Its density, calculated based on its chemical composition and unit cell parameters, is 8.16 g/cm³. Hardness has not been determined on the Mohs scale, but microhardness measurements indicate values typical for minerals of medium hardness. ## Colors and Varieties Malyshevit is uniform in color – it occurs in grayish-white shades, sometimes with a creamy or yellowish tint in reflected light. No varieties have been distinguished. ## History and Name The mineral was approved by the IMA in 2001 and first described in 2002 by a research group led by A.Y. Barkov. Its name commemorates the Russian geologist and mineralogist, Alexander Alexandrovich Malyshev (Александр Александрович Малышев), in recognition of his contribution to the study of the Norilsk deposits. The type locality (the only known one) is the Oktyabrskoye Cu-Ni deposit in the Norilsk region of Russia.
Diagnostic features
## Identification Identification of malyshevit is impossible without advanced analytical techniques. Due to the microscopic size of the grains and its occurrence in complex ore parageneses, it requires chemical composition analysis using an electron microprobe (EDS/WDS). In reflected light under an ore microscope, it exhibits a grayish-white color and weak anisotropy. ## Distinguishing from Similar Minerals It can be confused with many other sulfides and platinum-group metal (PGM) alloys, such as polarite, maslovite, majakite, or sobolevskite, as well as galena. Definitive distinction from these minerals is only possible based on precise chemical analysis. ## Crystal Forms It occurs exclusively as fine, anhedral (irregularly shaped) grains and inclusions in other ore minerals.
Geological environment
## Genesis Malyshevit is a hydrothermal mineral, crystallizing in the late stage of copper and nickel sulfide deposit formation. It forms in ore veins cutting through the ores. ## Mineral Associations It co-occurs with a rich assemblage of ore minerals. Most commonly, it is associated with: talnakhite, cubanite, polarite, maslovite, majakite, paolovite, sobolevskite, platinum-iron alloy, galena, sphalerite, pentlandite, and chalcopyrite. ## Localities The only confirmed locality in the world is the Oktyabrskoye deposit (Oktyabrsky mine) in the Talnakh region, near Norilsk, on the Taymyr Peninsula in Russia.
Rarity
Extremely rare
Collector aspects
## Quality Criteria In the case of such a rare micromineral, the primary criterion for value is the certainty of identification confirmed by analysis. Collectors value specimens where malyshevit grains are as "large" (on a micro scale) and clearly visible against the matrix as possible, as well as those rich in associated minerals. ## Popular Localities The only source of specimens is the type locality – the Oktyabrskoye deposit in Russia. Specimens are practically unavailable on the open market and are mainly found in institutional and specialized collections.
Care and storage
## Cleaning Specimens containing malyshevit, which are typically microscopic inclusions in other sulfides, should not be chemically cleaned. Only gentle dust removal with a soft brush or compressed air from a safe distance is permissible. ## What to Avoid Absolutely avoid contact with water, acids, detergents, and other chemicals, which can lead to oxidation and destruction of the mineral and associated minerals. As a sulfide, it is susceptible to degradation in a humid environment. ## Storage Store in a dry place, preferably in a sealed, lidded "micromount" box, to protect it from dust, moisture, and sudden temperature changes.