Buseckite
Chemical formula: (Fe<sup>2+</sup>,Zn<sup>2+</sup>,Mn<sup>2+</sup>)S<sup>2-</sup>
Buseckite is an extremely rare iron, zinc, and manganese sulfide, found mainly as microscopic grains in meteorites.
Properties
- Mohs hardness
- 4
- Luster
- Metallic
- Streak
- Black
- Density
- 4.09
- Cleavage
- Good on {1010} and {0001}
- Transparency
- Opaque
- Crystal system
- Hexagonal
Diagnostic features
## Identification Identification of buseckite is impossible without advanced analytical techniques. Due to its microscopic size and black color, it is visually indistinguishable from other fine-grained sulfides. Definitive identification requires chemical analysis using an electron microprobe (EDS/WDS) to determine the composition (dominance of Fe over Zn and Mn) and X-ray diffraction (XRD) to confirm the hexagonal structure. ## Distinguishing from Similar Minerals Buseckite can be confused with other sulfides of similar appearance, such as troilite, wurtzite, or sphalerite (especially its dark, iron-rich varieties). Differentiation is based solely on precise analysis of chemical composition and crystal structure. ## Crystal Forms This mineral forms irregular, anhedral grains or poorly developed, subhedral crystals ranging in size from submicrometer to several micrometers. It occurs as disseminated inclusions or in aggregates with other minerals.
Geological environment
## Genesis Buseckite forms under highly reducing, sulfur-rich conditions. Its primary environment of formation is sulfide inclusions in chondritic meteorites, where it crystallizes at high temperatures during processes occurring in the parent body of the asteroid. It has also been identified in terrestrial rocks, in the specific pyrometamorphic environment of the Hatrurim Formation in Israel, where it formed as a result of natural combustion of bituminous rocks at high temperature and low pressure. ## Mineral Associations In meteorites, buseckite coexists with troilite, daubréelite, and sphalerite. In rocks of the Hatrurim Formation, it is accompanied by tridymite and schreibersite. ## Localities The most important and confirmed localities for this mineral are the type locality – the Cahokia meteorite (Illinois, USA) and pyrometamorphic rocks from the Hatrurim Formation in Israel.
Rarity
Extremely rare
For collectors
## Quality Criteria As a microscopic mineral, buseckite is not evaluated based on typical aesthetic criteria such as color or luster. For collectors and scientific institutions, the quality and certainty of analytical identification are crucial. The value of a specimen is related to the abundance of buseckite grains in the matrix and the rarity of the parent material itself (e.g., a specific meteorite). ## Popular Localities The only sources for obtaining buseckite are fragments of the Cahokia meteorite and rocks from the Hatrurim Formation. These materials are not commonly available on the collector's market, and their circulation is primarily scientific.
Care and storage
## Cleaning Buseckite specimens are typically microscopic grains in polished meteorite sections or rocks. Cleaning in the traditional sense is neither possible nor necessary. If needed, the surface of the section can be wiped with a dry, soft microfiber cloth to remove dust. ## What to Avoid Contact with acids and other chemical reagents, which can destroy both buseckite and its surrounding matrix, must be strictly avoided. The specimen's surface should be protected from scratches and impacts. Ultrasonic cleaners should not be used. ## Storage Specimens containing buseckite, most often in the form of polished sections or microscopic preparations, should be stored in a dry place, in a specialized micromineral box or a membrane box, to protect them from dust and mechanical damage.