Lindqvistite
Chemical formula: Pb²⁺₂Mn²⁺Fe³⁺₁₆O₂₇
Lindqvistite is a rare lead, manganese, and iron oxide, forming small, hexagonal, tabular crystals with a metallic luster.
Properties
- Mohs hardness
- 6
- Color
- Black
- Luster
- Metallic
- Streak
- Brownish black
- Density
- 0
- Cleavage
- Perfect on {0001}
- Fracture
- Uneven
- Transparency
- Opaque
- Crystal system
- Hexagonal
Diagnostic features
## Identification Identification of lindqvistite is impossible without advanced analytical techniques. Visually, it appears as very small, black, hexagonal, tabular crystals with a metallic luster. Identification requires chemical analysis (EDS) and X-ray diffraction (XRD) to confirm its composition and crystal structure. ## Distinguishing from similar minerals It can be confused with other black, metallic minerals found in similar environments, such as magnetite, hematite, or other minerals from the magnetoplumbite supergroup (e.g., magnetoplumbite, plumboferrite). Differentiation is only possible based on detailed laboratory analyses. ## Crystal forms It forms thin, tabular crystals with a hexagonal outline, up to 0.2 mm in diameter and up to 0.02 mm thick.
Geological environment
## Genesis Lindqvistite forms in metamorphosed iron-manganese ore deposits. In its type locality (Långban, Sweden), it occurs in skarns, associated with oxides and silicates. ## Mineral associations It co-occurs with minerals such as andradite, calcite, hematite, and tephroite. ## Localities The only confirmed occurrence of this mineral worldwide is its type locality - the Långban deposit in Filipstad municipality, Värmland region, Sweden.
Rarity
Extremely rare
For collectors
## Quality criteria For collectors specializing in "microminerals" or systematic minerals, the value of a lindqvistite specimen depends on the presence of well-formed, albeit microscopic, crystals that can be identified on the rock matrix. Precise documentation and analytical confirmation of the mineral's identity are crucial. ## Popular localities The only source of specimens is the historic Långban mine in Sweden. Material from this locality is extremely prized and virtually unavailable on the commercial market, mainly originating from old museum collections and specialized private collections.
Care and storage
## Cleaning Specimens of lindqvistite, due to their microscopic size and fragility, should generally not be mechanically cleaned. If dust removal is necessary, compressed air can be used from a safe distance. Contact with water and chemicals should be avoided. ## What to avoid Contact with acids and other chemical agents must be strictly avoided. The mineral is brittle, so it should be protected from impacts and vibrations. It should not be heated or subjected to ultrasound. ## Storage Specimens should be stored in stable conditions, in a specialized "micromount" box, protecting them from dust, moisture, and mechanical damage. Mineral identification requires laboratory equipment, so preserving the original label with the location and catalog number is crucial.