Aleutite is a rare mineral known for its distinctive chemical composition and geological significance. It is both a vanadate and an arsenate mineral, but it can also be thought of as a natural salt-inclusion phase. It was discovered in the Second scoria cone of the Great Fissure Tolbachik eruption in Kamchatka, Russia, in summer 2015.
Aleutite is a fumarolic mineral discovered alongside several other newly discovered minerals in this locality. It was named after the Aleuts, the ethnic group that once lived on the Commander Islands in the Aleutsky District of Kamchatka Krai. This mineral is extremely brittle and dark red. Aleutite is a new structure type; it was refined as a two-component twin with a twin ratio of (0.955:0.045).
Identification
Aleutite crystals are found in masses of polycrystalline anhydrite. Aleutite is dark crimson, with a reddish black stripe and an adamantine shine. It is fragile, with no obvious cleavages. Parting was not detected, and the fracture was unequal. The density could not be measured since there was insufficient material. The computed specific gravity was 4.887 g/cm3.
- Formula mass: 287.26
- Color: Dark red
- Cleavage: none observed
- Fracture: Irregular/Uneven
- Tenacity: Brittle
- Luster: Adamantine
- Streak: Reddish black
- Diaphaneity: Transparent
- Density: 4.887 g/cm3
Characteristics
- Chemical Formula: It is a complex borosilicate mineral, often with additional elements such as calcium, aluminum, and fluorine.
- Color: Typically white, but can also exhibit shades of grey or colorless.
- Crystal System: Trigonal, meaning its crystal structure is based on a threefold rotational symmetry.
- Hardness: On the Mohs scale, aleutite usually has a hardness of around 5-6, making it relatively hard but not as hard as quartz.
- Luster: Generally vitreous, giving it a glass-like appearance.
- Transparency: Can range from transparent to translucent.
Occurrence
- Geological Environment: It is usually found in metamorphic rocks, particularly in regions that have undergone significant geological changes due to high pressure and temperature.
- Locations: It was first discovered in the Aleutian Islands, Alaska, which is how it got its name. However, it can also be found in other locations with similar geological conditions.
Significance
- Scientific Interest: It is of particular interest to geologists and mineralogists due to its complex structure and formation conditions. It provides insights into the processes occurring in the Earth’s crust under high-pressure conditions.
- Collecting: For mineral collectors, aleutite is a prized specimen due to its rarity and distinctive properties.
Applications
Aleutite doesn’t have significant industrial uses due to its rarity. Its primary value lies in research and collection.
