Muskoxite
Chemical formula: Mg<sub>7</sub>Fe<sup>3+</sup><sub>4</sub>(OH)<sub>26</sub>·H<sub>2</sub>O
Muskoxite is a rare mineral from the hydroxide group, forming microscopic, hexagonal platelets of a reddish-brown color.
Properties
- Mohs hardness
- 2.5
- Luster
- Vitreous, Pearly
- Streak
- Red-brown
- Density
- 2.8
- Cleavage
- Perfect on {0001}
- Fracture
- Micaceous
- Transparency
- Translucent to opaque
- Crystal system
- Trigonal
Diagnostic features
## Identification Field identification of muskoxite is practically impossible without specialized equipment. In a collection, it is identified based on its reddish-brown color, earthy appearance, very low hardness, and co-occurrence with serpentine minerals in a specific geological environment. Certain identification requires advanced methods such as X-ray diffraction (XRD) or chemical analysis. ## Distinguishing from Similar Minerals Muskoxite can be confused with other oxidation products of iron and magnesium minerals, such as goethite or earthy hematite. It is distinguished from them by its lower hardness, specific habit of microscopic crystals, and mineral associations, especially with coalingite and other magnesium hydroxides. ## Crystal Forms It forms microscopic, hexagonal (six-sided) platelets that aggregate into rosetted, felted, or earthy masses. It rarely occurs as veins visible to the naked eye cutting through the host rock.
Geological environment
## Genesis Muskoxite is a secondary mineral, formed by low-temperature hydrothermal processes or the weathering of serpentinized ultramafic rocks, such as peridotites and dunites. It forms in veins cutting through serpentinites, often as an alteration product of primary minerals rich in magnesium and iron. ## Mineral Associations It most commonly co-occurs with coalingite, lizardite, chrysotile, brucite, magnesite, iopyroaurite, as well as magnetite and chromite. ## Localities The most important and best-documented locality is its type locality – the Muskox Intrusion in the Northwest Territories, Canada. It is also known from several other places worldwide with similar geology, including Okayama Prefecture in Japan and the Bushveld Complex in South Africa.
Rarity
Very rare
For collectors
## Quality Criteria The quality of muskoxite specimens is primarily assessed based on the richness and purity of aggregates on the host rock. Specimens with clearly visible, though fine, veins of the mineral contrasting with serpentinite are most valued. The presence of well-defined associated minerals, especially coalingite, is also important. Due to the microscopic nature of the crystals, their individual form is not a criterion for evaluation. ## Popular Localities By far the most desired and classic specimens come from the type locality in the Muskox Intrusion, Canada. They are the standard for this mineral and form the basis of specialized collections.
Care and storage
## Cleaning Muskoxite specimens are very delicate and fragile. Mechanical cleaning should be avoided. If absolutely necessary, compressed air can be used to remove dust. Contact with water is not recommended due to possible reactivity and disintegration of aggregates. ## What to Avoid Contact with water, acids, and other chemicals must be strictly avoided. The mineral is sensitive to changes in humidity and temperature. It should not be heated or exposed to direct sunlight, which can cause its degradation. ## Storage Specimens should be stored in stable conditions, preferably in closed, padded boxes or "micromount" containers that protect against mechanical damage, dust, and humidity changes. Storage in damp rooms should be avoided.