Parawulffite

Chemical formula: K₅Na₃Cu₂+₈(S₆+O₄)₈O₄

Parawulffite is a very rare potassium, sodium, and copper sulfate, forming characteristic blue, tabular crystals in volcanic fumaroles.

## Characteristics Parawulffite is a complex potassium, sodium, and copper sulfate, occurring as small, well-formed crystals. It typically forms thin, tabular crystals with a hexagonal outline, often grouped into rosette-like or fan-shaped aggregates. Its intense blue color is one of its most distinctive visual features. ## Physical Properties Parawulffite crystals exhibit a vitreous luster. They are transparent to translucent. Due to the small size of the crystals, precise determination of hardness and density is difficult, but the hardness is estimated to be around 2.5 on the Mohs scale. It is a brittle mineral. ## Colors and Varieties This mineral occurs in a uniform, intense, azure or blue color. No color or commercial varieties are distinguished. ## History and Name Parawulffite was described in 2013 by a team of mineralogists (Filatov, Vergasova, Krivovichev, Burns, Ananiev). Its name refers to its structural similarity to wulffite (wulfenite), with the prefix "para-" indicating polymorphism – both minerals have the same chemical composition but differ in crystal structure. It was discovered in the products of fumarolic activity at Tolbachik volcano in Kamchatka, Russia. ## Uses Parawulffite has no industrial applications. It is solely an object of scientific and collecting interest due to its rarity, attractive appearance, and specific formation environment.

Properties

Mohs hardness: 2.5
Luster: Vitreous
Streak: Blue
Density: 3.44
Cleavage: Perfect on {010}
Fracture: Uneven
Transparency: Transparent to translucent
Crystal system: Monoclinic

Diagnostic features

## Identification Parawulffite can be identified by its intense blue color, tabular crystal habit with a hexagonal outline, and characteristic rosette-like aggregates. Its origin is also key – it occurs exclusively in the specific environment of high-temperature volcanic fumaroles. ## Differentiation from Similar Minerals It can be confused with other blue minerals from the fumaroles of Tolbachik volcano, such as piipite, lammerite, or euchlorine. Differentiation often requires advanced analytical methods, such as X-ray diffraction (XRD). Visually, the characteristic tabular habit and hexagonal outline of the crystals can be a helpful clue. ## Crystal Forms Parawulffite forms thin, tabular crystals, often with a hexagonal outline. These crystals typically occur as fan-shaped or rosette-like clusters and aggregates on the surface of the host rock.

Geological environment

## Genesis Parawulffite is a mineral of volcanic origin, formed by sublimation from volcanic gases in high-temperature fumaroles. It crystallizes on the surface of volcanic rocks at temperatures ranging from 450-480°C. ## Mineral Associations This mineral co-occurs with other rare fumarolic minerals, such as tenorite, hematite, halite, sylvine, langbeinite, aphthitalite, piipite, lammerite, euchlorine, urusovite, and johillerite. ## Localities The only confirmed locality of parawulffite in the world is its type locality – the "Arsenatnaya" fumarole on the second cinder cone of the Northern Breakthrough of the Great Fissure Eruption of Tolbachik volcano in Kamchatka, Russia.

Rarity

Very rare

For collectors

## Quality Criteria The most prized parawulffite specimens are those with well-formed, sharp crystals of intense blue color, forming aesthetic, rosette-like aggregates. Contrast with the light host rock and absence of mechanical damage are also important. Due to the microscopic nature of most specimens, the size of crystals and aggregates significantly increases their value. ## Popular Localities The only source of parawulffite specimens is Tolbachik volcano in Kamchatka. Specimens from this locality, especially those collected during or shortly after eruptions, are highly sought after by collectors specializing in rare minerals and volcanic minerals.

Care and storage

## Cleaning Parawulffite specimens are extremely delicate and potentially water-soluble. Cleaning should be kept to an absolute minimum. If necessary, compressed air can be used very carefully to remove loose dust particles. Any contact with water and other liquids should be avoided. ## What to Avoid Contact with water, acids, detergents, and other chemicals that can dissolve or damage the mineral must be strictly avoided. The crystals are very brittle and susceptible to mechanical damage. They should be protected from high temperatures and sudden temperature changes, as well as from humid air. ## Storage Parawulffite specimens should be stored under stable, dry conditions. The best solution is a tightly sealed "perky box" away from direct sunlight and heat sources. Due to its fragility, avoid placing anything on the specimen.

Sources

IMA Mineral List (CNMNC)