Artroeite
Chemical formula: Pb<sup>2+</sup>AlF<sub>3</sub>(OH)<sub>2</sub>
Artroeite is a rare aluminum lead fluoride, forming colorless, tabular crystals with a vitreous luster.
Properties
- Mohs hardness
- 3
- Luster
- Vitreous
- Streak
- White
- Density
- 4.35
- Cleavage
- Good on {010}
- Fracture
- Uneven
- Transparency
- Transparent
- Crystal system
- Monoclinic
Diagnostic features
## Identification Identification of artroeite requires advanced research methods, such as chemical analysis (EDS) and X-ray diffraction (XRD), due to its small size and similarity to other secondary minerals. Visually, it is characterized by the presence of small, colorless, tabular crystals with a vitreous luster, often associated with other rare minerals. ## Distinguishing from Similar Minerals It can be confused with other colorless secondary minerals from the oxidation zone, such as anglesite, cerussite, or gearksutite. Differentiation is almost exclusively possible based on chemical composition analysis, which will reveal the presence of lead, aluminum, and fluorine. ## Crystal Forms Artroeite forms thin, tabular crystals with a hexagonal or rhombic outline, often flattened. It occurs as single crystals or small groups and aggregates growing on other minerals.
Geological environment
## Genesis Artroeite is a secondary mineral, forming in the oxidation zones of hydrothermal lead-zinc ore deposits. It forms as a result of the action of fluorine-rich solutions on primary lead-bearing minerals, in the presence of aluminum derived from the decomposition of surrounding rock minerals (e.g., feldspars). ## Mineral Associations This mineral co-occurs with other rare secondary minerals. In its type locality (Grand Reef Mine), it was found in association with anglesite, galena, sphalerite, quartz, as well as rarer minerals such as gearksutite, cryolite, sellaite, and pseudoboleite. ## Localities The only confirmed and thoroughly described occurrence of artroeite in the world is its type locality – the Grand Reef Mine, located in the Santa Teresa Mountains in Graham County, Arizona, USA.
Rarity
Extremely rare
For collectors
## Quality Criteria The quality of an artroeite specimen primarily depends on the presence of well-formed, sharp, and undamaged crystals, even if they are microscopic in size. Specimens where crystals are clearly visible, transparent, and contrast with the matrix are highly valued. The presence of rare associated minerals also increases its collector's value. ## Popular Localities The only source of artroeite specimens is the Grand Reef Mine in Arizona. Material from this locality is extremely rare and sought after by specialized collectors of rare minerals and collectors specializing in minerals from specific localities (so-called "locality collectors").
Care and storage
## Cleaning Due to its brittleness and rarity, mechanical cleaning is not recommended. If absolutely necessary, compressed air can be used to remove dust. Avoid contact with water and any chemicals. ## What to Avoid Avoid ultrasonics, steam cleaners, acids, solvents, and sudden temperature changes. The mineral is soft and brittle, susceptible to mechanical damage. ## Storage Artroeite specimens should be stored in stable conditions, in a closed display box, away from light, dust, and moisture. It is best to store it in its original container (if purchased as such) to avoid scratches and contact with other minerals.