Cadsulfohite
Chemical formula: Cd₂(S⁶⁺O₄)(OH)₂
Cadsulfohite is a very rare, secondary cadmium sulfate, forming microscopic, colorless crystals, found so far in only one location worldwide.
Properties
- Luster
- Vitreous to adamantine
- Streak
- White
- Density
- 5.25
- Transparency
- Transparent
- Crystal system
- Monoclinic
Diagnostic features
## Identification Identification of cadsulfohite is possible only through advanced analytical methods, such as Raman spectroscopy or electron microprobe chemical analysis (EDS/WDS). Visual identification in the field or even in a collection is impossible due to its microscopic size and lack of characteristic macroscopic features. ## Differentiation from Similar Minerals It can be confused with other secondary, colorless sulfates or oxide minerals found in the oxidation zones of ore deposits, such as gypsum, anglesite, or hemimorphite. Differentiation requires specialized analytical equipment. ## Crystal Forms It forms elongated, bladed or acicular crystals, often gathered in small, radial or chaotic aggregates. The crystals are too small to observe their structural details with the naked eye.
Geological environment
## Genesis Cadsulfohite is a secondary mineral, formed in the oxidation zone (gossan) of polymetallic hydrothermal deposits rich in cadmium sulfides (like greenockite) and zinc (sphalerite). It forms under low-temperature conditions as a result of the weathering of primary ores. ## Mineral Associations At the only known locality (Tsumeb), it co-occurs with other rare secondary minerals, such as greenockite, otavite, sphalerite, tennantite, galena, anglesite, and gypsum. ## Localities The only confirmed occurrence of cadsulfohite in the world is the Tsumeb mine (Ongopolo Mine) in the Oshikoto Region, Namibia. This is the so-called type locality for this mineral.
Rarity
Extremely rare
For collectors
## Quality Criteria Due to its extreme rarity, every analytically confirmed cadsulfohite specimen is valuable. Microscopic specimens with well-formed, isolated crystals set on a contrasting rock matrix are most highly valued. The size of aggregates and the abundance of occurrence on the sample also increase its value. ## Popular Localities The only source of specimens is historical material from the Tsumeb mine in Namibia. New finds are practically impossible, as the mine is closed and flooded.
Care and storage
## Cleaning Cadsulfohite specimens are extremely delicate and small, so mechanical or chemical cleaning is not recommended. The safest way to remove dust is by using compressed air from a safe distance. ## What to Avoid Avoid contact with water, acids, bases, and all solvents. The crystals are brittle and sensitive to shocks and temperature changes. They should not be heated or exposed to direct sunlight. ## Storage Specimens should be stored exclusively in specialized, sealed "micromount" boxes, protecting them from dust, moisture, and mechanical damage. Display is possible only under a microscope.