Sverigeite
Chemical formula: NaBe<sub>2</sub>Mn<sup>2+</sup><sub>2</sub>Sn<sup>4+</sup>Si<sub>3</sub>O<sub>12</sub>(OH)
Sverigeite is a rare mineral from the silicate group, distinguished by its unique chemical composition containing sodium, beryllium, manganese, and tin.
Properties
- Mohs hardness
- 6.5
- Luster
- Vitreous
- Streak
- Pale yellow
- Density
- 3.58
- Cleavage
- Good on {010}
- Fracture
- Uneven
- Transparency
- Transparent to translucent
- Crystal system
- Orthorhombic
Diagnostic features
## Identification Amateur identification of sverigeite is practically impossible and requires advanced analytical methods, such as chemical analysis (EDS/WDS) or X-ray diffraction (XRD). A preliminary indication may be its yellowish-brown color, vitreous luster, and occurrence in association with minerals from Långban. ## Distinguishing from Similar Minerals It can be confused with other rare silicates from Långban, such as welinite or manganhumite. Definitive differentiation is possible only based on chemical composition analysis, especially confirming the presence of tin and beryllium. ## Crystal Forms It forms small, platy or short-prismatic crystals with a cross-section close to square. It usually occurs as single, embedded grains or small aggregates.
Geological environment
## Genesis Sverigeite forms as a result of metamorphic processes in iron and manganese ore deposits. It occurs in skarns and hematite lenses within metamorphic carbonate rocks (dolomitic marbles). ## Mineral Associations This mineral co-occurs with other minerals typical of the Långban deposit, such as calcite, diopside, phlogopite, hematite, magnetite, welinite, tephroite, richterite, berzeliite, and hausmannite. ## Localities The only confirmed locality of sverigeite in the world is its type locality – the Långban mine in the Värmland region of Sweden. This is one of the most famous mineralogical sites in the world, known for the occurrence of unique and rare minerals.
Rarity
Extremely rare
For collectors
## Quality Criteria The most important value criterion for collectors is the size and quality of crystal formation, which is rare for sverigeite. Specimens with clearly visible, well-formed crystals of intense, yellowish-brown color are highly prized. An aesthetic rock matrix and association with other rare minerals from Långban are also important. ## Popular Localities The only source of sverigeite specimens is the historic Långban mine in Sweden. Material from this locality is extremely valued and sought after by collectors specializing in rare or systematic minerals.
Care and storage
## Cleaning Utmost caution is recommended. The safest method is to use compressed air to remove dust. If wet cleaning is necessary, use only distilled water and a very soft brush, avoiding strong friction. The specimen should be thoroughly dried immediately. ## What to Avoid Absolutely avoid all chemicals, including acids and strong bases, which can damage the mineral. Ultrasonic cleaners should not be used. The mineral is sensitive to rapid temperature changes. ## Storage Sverigeite specimens, being extremely rare and usually small, should be stored under stable conditions in a sealed "micromount" box, protecting them from dust, moisture, and mechanical damage. Avoid exposure to direct sunlight.