Metaswitzerite
Chemical formula: Mn<sup>2+</sup><sub>3</sub>(PO<sub>4</sub>)<sub>2</sub>·4H<sub>2</sub>O
Metaswitzerite is a rare, hydrated manganese phosphate, forming brittle, platy crystals of a straw-yellow color.
Properties
- Mohs hardness
- 2.5
- Luster
- Vitreous to pearly
- Streak
- Light yellow
- Density
- 2.95
- Cleavage
- Perfect on {010}
- Fracture
- Uneven
- Transparency
- Transparent to translucent
- Crystal system
- Monoclinic
Diagnostic features
## Identification Key diagnostic features of metaswitzerite include its platy, micaceous habit, low hardness (about 2.5), perfect cleavage, and straw-yellow color. An important indicator is its occurrence as an alteration product of switzerite in a phosphate-rich environment. ## Distinguishing from Similar Minerals Metaswitzerite can be confused with other platy minerals, such as muscovite or other yellow secondary phosphates. It is distinguished from muscovite by its significantly lower hardness and less flexible flakes. Identification is aided by the analysis of associated minerals, typical of phosphate pegmatites. Certain differentiation often requires chemical analysis. ## Crystal Forms It forms tabular or platy crystals, often grouped into fan-shaped, radial, or leafy aggregates. Commonly found as pseudomorphs after switzerite crystals.
Geological environment
## Genesis Metaswitzerite is a secondary mineral. It forms as a result of partial dehydration of switzerite, usually due to changes in the environment, such as exposure to drier air. Switzerite, its precursor, crystallizes in phosphate-rich zones within complex granitic pegmatites. ## Mineral Associations It most often co-occurs with switzerite, as well as with other phosphate minerals typical of pegmatites, such as vivianite, triplite, beusite, strengite, and rockbridgeite. ## Localities The most important and classic localities for metaswitzerite include sites known for high-quality switzerite. These are primarily the Foote Lithium Co. Mine in Kings Mountain (North Carolina, USA) and the Big Fish River and Rapid Creek area (Yukon, Canada).
Rarity
Very rare
For collectors
## Quality Criteria Specimens with well-formed, distinct flakes, forming aesthetic aggregates, are most valued by collectors. The intensity and purity of the straw-yellow color and the absence of mechanical damage are important. A clear pseudomorph after switzerite or an association with other rare phosphates from a given locality adds additional value. ## Popular Localities Specimens of the highest collector's value come from two famous phosphate localities: the Foote Mine in North Carolina (USA) and the Rapid Creek area in Yukon (Canada).
Care and storage
## Cleaning Metaswitzerite specimens are very delicate and should be cleaned with the utmost care. It is recommended to remove dust only dry, using a soft brush. Avoid washing with water, as, being a dehydration product, it may be sensitive to changes in humidity. The use of ultrasonic cleaners is prohibited. ## What to Avoid The mineral is soft, brittle, and has perfect cleavage, so it should be protected from impacts, scratching, and vibrations. Avoid contact with chemicals and sudden changes in temperature and humidity, which could affect its structure. ## Storage It is recommended to store specimens in separate, padded boxes to prevent mechanical damage and contact with harder minerals. It is best kept in a stable environment, away from dust and direct sunlight.