Werdingite

Chemical formula: Mg₂Al₁₄Si₄B₄O₃₇

Werdingite is a very rare magnesium, aluminum, and boron silicate, forming radial aggregates of small, prismatic crystals.

## Characteristics Werdingite is a complex boron, magnesium, and aluminum silicate, occurring extremely rarely. It forms clusters of small, elongated prismatic crystals, which often arrange themselves into radial or fan-shaped aggregates. Individual crystals rarely exceed 1 mm in length. Due to its chemical composition and structure, it is closely related to minerals such as kornerupine and boralsilite. ## Physical Properties This mineral is characterized by significant hardness, approximately 7 on the Mohs scale. It has a vitreous luster and is usually translucent. The density of werdingite has been calculated at 3.12 g/cm³. ## Colors and Varieties Werdingite occurs in shades from pale yellow to yellowish-green. Some specimens may be almost colorless. No varieties have been distinguished. ## History and Name The mineral's name honors Günter Werding (born 1947), a German mineralogist from the Ruhr University Bochum, who made significant contributions to the study of boron silicates. Werdingite was first described in 1990 based on material found at its type locality in Bok se Pyin, Mandalay Region, Myanmar (Burma).

Properties

Mohs hardness: 7
Luster: Vitreous
Streak: White
Density: 3.12
Cleavage: Good on {010} and {110}
Fracture: Uneven
Transparency: Translucent
Crystal system: Triclinic

Diagnostic features

## Identification A key diagnostic feature of werdingite is its characteristic radial aggregates composed of small, prismatic crystals of a pale yellow or yellowish-green color. High hardness (approx. 7) is also an important indicator. However, final confirmation requires advanced analytical methods such as X-ray diffraction (XRD) or chemical analysis (EDS/WDS). ## Distinguishing from Similar Minerals Werdingite can be confused with other rare boron silicates, such as kornerupine or grandidierite, which can form similar aggregates and have comparable colors. Differentiation with the naked eye is practically impossible and requires specialized laboratory equipment. ## Crystal Forms Werdingite crystallizes as slender, elongated prisms. These crystals almost always occur in radial or fan-shaped aggregates, and less frequently form fibrous clusters.

Geological environment

## Genesis Werdingite is a mineral of metamorphic origin. It forms under high-temperature conditions in aluminum- and boron-rich, silica-poor rocks. At the type locality (Myanmar), it was found in xenoliths of calc-silicate rocks within a granitic intrusion. ## Mineral Associations This mineral co-occurs with minerals such as corundum (sapphire), sinhalite, kornerupine, spinel, hibonite, diaspore, tourmaline (dravite group), and boralsilite. ## Localities Confirmed occurrences of werdingite are extremely rare. The most important ones include: - **Myanmar (Burma)**: Bok se Pyin in the Mandalay Region - type locality. - **Madagascar**: Ihosy Region, Fianarantsoa Province. - **Tajikistan**: Kukhi-Lal Mine in the Pamir Mountains.

Rarity

Very rare

For collectors

## Quality Criteria The most prized werdingite specimens are those that exhibit well-formed, radial aggregates with distinct, individual crystals. The intensity and purity of the yellow or yellowish-green color also increase the value of the specimen. Due to its rarity, any well-documented specimen, even in micro form, is considered valuable. ## Popular Localities Specimens from the type locality in Myanmar (Burma) and from Madagascar are the most renowned in the collecting world, although material from both locations is extremely difficult to acquire.

Care and storage

## Cleaning It is recommended to clean only with compressed air to remove dust. Due to its rarity and the delicacy of the aggregates, contact with water and any chemical agents should be avoided. ## What to Avoid Avoid ultrasonic cleaners, steam cleaning, and sudden temperature changes. Protect from acids and other chemicals. Prolonged exposure to strong sunlight is not advisable. ## Storage Werdingite specimens should be stored in stable conditions, preferably in a closed display box, to protect them from dust and mechanical damage. Due to the small size of the crystals, a "micromount box" is an ideal solution.

Sources

IMA Mineral List (CNMNC)