Miserite
Chemical formula: K₁.₅-x(Ca,Y,REE)₅[Si₆O₁₅][Si₂O₇](OH,F)₂·yH₂O
Miserite is a rare potassium, calcium, and rare-earth element silicate, distinguished by its characteristic pinkish-purple color and complex structure.
Properties
- Mohs hardness
- 5.5-6
- Color
- Pink, red-brown, raspberry-red
- Luster
- Vitreous
- Streak
- White
- Density
- 2.84
- Cleavage
- Perfect on {100}, imperfect on {010}.
- Fracture
- Irregular/Uneven,Sub-Conchoidal
- Transparency
- Translucent
- Crystal system
- Triclinic
Diagnostic features
## Identification The key diagnostic feature of miserite is its characteristic pinkish-purple color combined with its massive or fibrous habit. Hardness (5.5-6) and mineral associations (e.g., wollastonite, ekanite) in a specific geological environment (syenites) are also important indicators. ## Distinguishing from Similar Minerals At first glance, miserite can be confused with rhodonite, eudialyte, or tugtupite. It is usually distinguished from rhodonite by the absence of black manganese oxide inclusions and a slightly different pink hue. Eudialyte crystallizes in a different system and occurs in distinct associations. Tugtupite exhibits strong fluorescence and is often redder. ## Crystal Forms Well-formed crystals are extremely rare. If they occur, they take the form of small, platy or bladed crystals with triclinic symmetry. Most commonly, it is found as compact, felted masses or radial and fibrous aggregates.
Geological environment
## Genesis Miserite is a mineral of metamorphic and metasomatic origin. It forms as a result of hydrothermal solutions interacting with silicate-carbonate rocks within alkaline rock intrusions, such as nepheline syenites and associated pegmatites. ## Mineral Associations This mineral often co-occurs with quartz, microcline, calcite, wollastonite, diopside, titanite, apophyllite, as well as rarer minerals like ekanite, scapolite, or turkestanite. ## Localities The most important and well-known locality, from which the best specimens originate, is the Dara-i-Pioz massif in Tajikistan. Other confirmed localities include Mont Saint-Hilaire in Quebec (Canada) and the Aldan River region in Siberia (Russia). Occurrences in Arkansas (USA), from which the type specimen originates, provide material of significantly lower collector quality.
Rarity
Rare
For collectors
## Quality Criteria The most highly prized miserite specimens are characterized by an intense, uniform, pinkish-purple color. Large, miserite-rich rock fragments from the Dara-i-Pioz massif in Tajikistan are the most sought after. Specimens with visible, even if small, crystals are exceptionally rare and valuable. Contrast with white or gray matrix rock (e.g., with wollastonite) enhances visual appeal. ## Popular Localities Undoubtedly, the most important locality for collectors is the Dara-i-Pioz massif in Tajikistan. Specimens from Mont Saint-Hilaire in Canada are also valued, though usually smaller and rarer. Material from the original locality in Arkansas (USA) is mainly of historical significance.
Care and storage
## Cleaning Miserite specimens should be cleaned gently, using a soft brush and distilled water. Ultrasonic cleaners should be avoided, as they can damage fibrous aggregates. ## What to Avoid The mineral is sensitive to strong acids, which can damage it. It should be protected from sudden temperature changes and prolonged exposure to direct sunlight, although its distinct effect on fading is not known. ## Storage It is recommended to store specimens in separate, padded boxes or display cases to prevent scratching by harder minerals. Stable humidity and temperature conditions should be ensured.