Belogubite
Chemical formula: Cu<sup>2+</sup>Zn<sup>2+</sup>(S<sup>6+</sup>O<sub>4</sub>)<sub>2</sub>·10H<sub>2</sub>O
Belogubite is a very rare, water-soluble copper and zinc sulfate, forming blue-green, acicular crystals.
Properties
- Mohs hardness
- 2
- Luster
- Vitreous
- Streak
- Light blue
- Density
- 2.11
- Cleavage
- Perfect on {100}
- Fracture
- Uneven
- Transparency
- Transparent
- Crystal system
- Triclinic
Diagnostic features
## Identification Belogubite can be identified by its characteristic form – it creates very fine, acicular or fibrous crystals of a blue-green color. It occurs as an oxidation product of sulfides in a mining environment. A key diagnostic feature is its complete solubility in water. ## Distinguishing from Similar Minerals It can be confused with other secondary copper sulfates, such as chalcanthite (CuSO₄·5H₂O) or kröhnkite (Na₂Cu(SO₄)₂·2H₂O). However, chalcanthite usually forms larger, better-formed crystals with an intense blue color. Final differentiation from other rare copper and zinc sulfates requires advanced chemical (EDS) and crystallographic (XRD) analyses. ## Crystal Forms Belogubite crystals are strongly elongated, acicular, often with a bladed cross-section. They usually occur as tangled, woolly or felt-like aggregates, as well as crusts and efflorescences on the host rock.
Geological environment
## Genesis Belogubite is a secondary mineral, formed in the oxidation zones of polymetallic sulfide deposits. It forms as a result of the weathering of primary minerals containing copper and zinc, under low-temperature conditions. It is a mineral typical of mining environments, where it forms as a product of post-mining processes on excavation walls. ## Mineral Associations At the type locality (Gayskoye deposit, Russia), belogubite co-occurs with other secondary sulfates, such as chalcanthite, epsomite, gypsum, gunningite, hexahydrite, pickeringite, and szomolnokite. ## Localities The only confirmed and described occurrence of belogubite in the world is its type locality: the Gayskoye copper-zinc ore deposit in the Orenburg Oblast, Southern Urals, Russia.
Rarity
Extremely rare
For collectors
## Quality Criteria The quality of a belogubite specimen primarily depends on the abundance and accumulation of its acicular crystals on the host rock. The most valued specimens are those with dense, fluffy aggregates of an intense, blue-green color, contrasting well with the matrix. Due to the microscopic size of the crystals, their individual form is not the main criterion for evaluation. ## Popular Localities The only source of belogubite specimens is the Gayskoye mine in the Urals, Russia. All specimens available on the collector's market come from this single locality.
Care and storage
## Cleaning The mineral must not be cleaned wet under any circumstances, as it is completely water-soluble. Any contact with water, even in the form of vapor, leads to its destruction. Dust can be removed very carefully using a soft brush or a stream of compressed air from a safe distance. ## What to Avoid Contact with water, moisture, water vapor, and all chemicals must be strictly avoided. Belogubite is hygroscopic and unstable in conditions of elevated air humidity – it can absorb water and undergo dehydration or decomposition. It should be protected from temperature changes and direct sunlight. ## Storage Belogubite specimens require storage in conditions of controlled, low humidity. The best solution is a sealed container (e.g., a "perky box") with a desiccant (e.g., silica gel). Storage in a dry and temperature-stable place is crucial for preserving the specimen.