Parádsasvárite
Chemical formula: Zn<sup>2+</sup><sub>2</sub>(CO<sub>3</sub>)(OH)<sub>2</sub>
Parádsasvárite is a rare zinc hydroxycarbonate, forming small, spherical aggregates with a silky luster, closely related to hydrozincite.
Properties
- Mohs hardness
- 2-2.5
- Luster
- Silky
- Streak
- White
- Density
- 3.65
- Cleavage
- Perfect on {100}
- Fracture
- Uneven
- Transparency
- Translucent
- Crystal system
- Monoclinic
Diagnostic features
## Identification Parádsasvárite can be identified by its characteristic mode of occurrence – small, white, spherical aggregates with a radial-fibrous structure and silky luster. A key diagnostic feature is its vigorous reaction with acids. Due to its similarity to other secondary zinc minerals, final identification requires advanced analytical methods, such as X-ray diffraction (XRD). ## Distinguishing from Similar Minerals Parádsasvárite is visually almost identical to hydrozincite. It differs from it in crystal structure (parádsasvárite crystallizes in the monoclinic system, while hydrozincite is orthorhombic), which is impossible to determine without specialized equipment. It can also be confused with other white, fibrous carbonates or sulfates, but its reaction with acid and co-occurrence with other zinc minerals are strong indicators. ## Crystal Forms This mineral forms spherulitic (spherical) and radial aggregates, composed of tiny, elongated crystals with a bladed or acicular habit. Single, well-formed crystals are extremely rare and microscopic in size.
Geological environment
## Genesis Parádsasvárite is a secondary mineral, formed in the oxidation (weathering) zones of zinc ore deposits. It forms as a result of carbon dioxide-rich waters acting on other zinc minerals, such as sphalerite. It forms under low temperature and pressure conditions, often in voids and fractures in rocks. ## Mineral Associations It most commonly co-occurs with the mineral to which it is closely related – hydrozincite. It is also accompanied by other minerals of the oxidation zone, such as smithsonite, hemimorphite, aurichalcite, as well as primary minerals, mainly sphalerite and galena, and gangue minerals like calcite and dolomite. ## Localities The most important and type locality for parádsasvárite is the ore mine in Parádsasvár in the Mátra Mountains, Hungary, from where the best-known specimens originate. It has also been reported in several other locations worldwide, including mines in Carinthia, Austria, and Gifu Prefecture, Japan. Everywhere it is a very rare mineral.
Rarity
Very rare
For collectors
## Quality Criteria The most prized parádsasvárite specimens are those that have well-formed, spherical aggregates with a distinct silky luster, set on a contrasting rock matrix. Due to the small size of the aggregates (usually 1-3 mm), specimens with spherulite diameters exceeding 5 mm are considered exceptional. Aesthetic composition and the absence of damage to the delicate fibers are also important. ## Popular Localities The only source of high-quality collector specimens is the type locality – Parádsasvár, Hungary. Specimens from other locations are extremely rare and are primarily of scientific interest.
Care and storage
## Cleaning Parádsasvárite specimens are extremely delicate and fragile. Cleaning should be kept to an absolute minimum. Only careful removal of dust with a soft brush or a stream of compressed air from a safe distance is permissible. Avoid contact with water, which can damage the delicate, fibrous aggregates. ## What to Avoid This mineral is sensitive to all chemicals, especially acids, in which it rapidly dissolves with the release of carbon dioxide. It should be protected from moisture, high temperatures, and mechanical shocks and impacts. Due to its fragility, it should not be touched with fingers. ## Storage It is recommended to store parádsasvárite specimens exclusively in closed, padded "micromount" boxes to protect them from dust, moisture, and mechanical damage. Display should be in stable conditions, away from sources of vibration and direct sunlight.