Parwanite

Chemical formula: NaMg<sub>4</sub>Al<sub>8</sub>(PO<sub>4</sub>)<sub>8</sub>(CO<sub>3</sub>)(OH)<sub>7</sub>·30H<sub>2</sub>O

Parwanite is an extremely rare, hydrated phosphate-carbonate mineral of blue color, found as microscopic rosettes.

## Characteristics Parwanite is a very rare secondary mineral, occurring as small, spherical aggregates and rosettes. The individual crystals forming these aggregates are extremely small, having the form of lamellae or needles, and reaching sizes up to 20 micrometers in length and only 1 micrometer in thickness. Due to the microscopic size of the crystals, its physical characteristics are difficult to observe with the naked eye. ## Physical Properties Parwanite crystals exhibit a silky luster. Due to its occurrence as fine aggregates, hardness and density have not been precisely determined. ## Colors and Varieties This mineral is characterized by a pale blue to blue color. No varieties have been distinguished. ## History and Name Parwanite was discovered in 1994 in a phosphate quarry near Angaston, South Australia. Its name comes from the word "parwan," which means "cloud" in the local Aboriginal language, referring to the pale blue color and appearance of the mineral aggregates. It was approved by the International Mineralogical Association (IMA) in 1996.

Properties

Luster
Silky
Streak
Pale blue
Transparency
Translucent
Crystal system
Orthorhombic

Diagnostic features

## Identification Amateur identification of parwanite is practically impossible. Identification requires advanced laboratory techniques such as X-ray diffraction (XRD) and chemical analysis (EDS/WDS). It is distinguished by its pale blue color and occurrence in the form of microscopic, spherical aggregates. ## Distinguishing from Similar Minerals It can be confused with other secondary phosphate minerals of similar color and form of occurrence, such as wavellite or turquoise. Definitive differentiation is possible only through chemical and structural analysis. ## Crystal Forms Parwanite forms spherical aggregates (spherulites) and rosettes up to 0.1 mm in diameter, composed of radially arranged, lamellar or acicular crystals.

Geological environment

## Genesis Parwanite is a secondary mineral, formed in the weathering zones of phosphate deposits. It forms as a result of the action of hydrothermal solutions or surface waters on rocks rich in aluminum and phosphorus. In the type locality (Angaston, Australia), it formed in voids within a siliceous-phosphatic breccia. ## Mineral Associations At the type locality, it co-occurs with quartz, apatite, crandallite, wavellite, strengite, and minyulite. ## Localities The only confirmed occurrence of parwanite in the world is the phosphorite quarry near Angaston, in the Mount Lofty Ranges, South Australia.

Rarity

Extremely rare

For collectors

## Quality Criteria As a microscopic mineral, parwanite is valued primarily by collectors specializing in rare minerals and "micromount" specimens. The value of a specimen is determined primarily by the abundance and good development of spherical aggregates on the rock matrix, as well as the intensity of the blue color. Specimens with clearly visible, numerous parwanite rosettes are most desirable. ## Popular Localities The only source of specimens is its type locality in Angaston, South Australia.

Care and storage

## Cleaning Parwanite specimens are extremely delicate and susceptible to damage. Mechanical or chemical cleaning is not recommended. Any attempts at cleaning may destroy the microscopic crystals. It is best to leave the specimen in its untouched state. ## What to Avoid Contact with water, chemicals, ultrasound, and sudden temperature changes must be strictly avoided. As a hydrated mineral, it can undergo dehydration in a dry environment or under heat, leading to its destruction. ## Storage It is recommended to store specimens exclusively in closed, stable containers (e.g., "micromount" type) to protect them from dust, moisture, and mechanical damage. Avoid exposure to direct sunlight.

Sources

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