Vuorelainenite
Chemical formula: Mn²⁺V³⁺₂O₄
Vuorelainenite is a rare mineral from the spinel group, an oxide of manganese and vanadium, found as small, black, metallic grains.
Properties
- Mohs hardness
- 6.5
- Luster
- Metallic
- Streak
- Grayish brown
- Density
- 0
- Cleavage
- None
- Fracture
- Uneven
- Transparency
- Opaque
- Crystal system
- Isometric
Diagnostic features
## Identification Identification of vuorelainenite is impossible without advanced laboratory techniques, such as chemical analysis (EDS/WDS) and X-ray diffraction (XRD). In collecting conditions, identification relies on trust in the label and the reputation of the supplier. Visually, they are simply tiny, black, metallic-lustered grains in the rock. ## Distinguishing from Similar Minerals It can be confused with many other black, metallic minerals from the spinel group, such as magnetite, chromite, or franklinite, as well as other oxides. Definitive differentiation is possible only based on chemical composition, especially the characteristic presence of vanadium and manganese. ## Crystal Forms Vuorelainenite forms fine, granular aggregates and very small, most often octahedral crystals, typical for minerals of the spinel group. Crystals rarely exceed a few tens of micrometers in size.
Geological environment
## Genesis Vuorelainenite forms as a result of metamorphic processes in metal sulfide deposits. It crystallizes in metamorphic rocks rich in manganese and vanadium, under amphibolite facies conditions. It is a product of the alteration of earlier minerals. ## Mineral Associations This mineral co-occurs with other vanadium and manganese minerals. In its type locality (Outokumpu, Finland), it was found in association with karelianite, eskolaite, chromite, pyrophanite, sphalerite, pyrite, chalcopyrite, and quartz. It also occurs with nolanite and schreyerite. ## Localities The most important and confirmed occurrences of vuorelainenite worldwide are: - Sätra Mine in Doverstorp, Finspång municipality, Sweden – considered the source of the best known specimens. - Outokumpu copper ore deposit in Finland – the type locality. - Benallt zinc deposit in Rhiw, on the Llŷn Peninsula, Wales, United Kingdom. - Lake Wilson area in Labrador, Canada.
Rarity
Very rare
For collectors
## Quality Criteria The quality of a vuorelainenite specimen primarily depends on the abundance and size of the grains or crystals within the host rock. Since the crystals are microscopic, any specimen with visible aggregates, either to the naked eye or under slight magnification, is considered exceptional. Contrast with a light host rock (e.g., quartz) enhances visual appeal. ## Popular Localities The most prized specimens by collectors, featuring relatively large (for this mineral) crystals, come from the Sätra mine in Sweden.
Care and storage
## Cleaning Specimens containing vuorelainenite are usually not cleaned due to the microscopic nature of the grains and their embedding in the host rock. Any mechanical intervention, even with a soft brush, risks damage or loss of material. ## What to Avoid Avoid contact with chemicals, especially strong acids, which can react with the mineral or surrounding rock. Ultrasonic cleaners and steam cleaning should also be avoided. ## Storage Specimens should be stored in stable conditions, away from dust and moisture, preferably in a sealed "micromount" box. Protect from impacts and shocks that could cause small grains to chip off.