Alvanite

Alvanite is a rare zinc–nickel–aluminum vanadate mineral with the formula (Zn,Ni)Al₄(V⁵⁺O₃)₂(OH)₁₂·2H₂O. It was first discovered in the Karatau Mountains of Kazakhstan and is notable for its unusual combination of aluminum and vanadium in a hydrated framework.

🌍 Origins and Naming

• Name Origin: Derived from ALuminum and VANadium in its composition.
• Discovery: First described in 1959, approved by the IMA.
• Type Locality: Kurumsak and Balasauskandyk districts, northwestern Karatau Mountains, Kazakhstan.

🔬 Chemical and Structural Properties

• Formula: (Zn,Ni)Al₄(V⁵⁺O₃)₂(OH)₁₂·2H₂O
• Crystal System: Monoclinic, point group 2/m.
• Appearance:
  • Color: Pale bluish-green to bluish-black.
  • Habit: Thin hexagonal platelets, micaceous aggregates.
  • Luster: Vitreous to pearly.
  • Streak: White.
• Hardness: 3–3.5 on Mohs scale.
• Specific Gravity: ~2.49.
• Optical Properties: Biaxial (–), semitransparent, with strong dispersion.

⚙️ Geological Occurrence

• Environment: Found in the oxidation zones of vanadium-bearing clay–anthraxolite horizons.
• Associated Minerals: Often occurs with other vanadates and secondary oxidation products.
• Localities:
  • Karatau Mountains, Kazakhstan (type locality).
  • Rarely reported elsewhere; considered a very uncommon mineral.

📖 Scientific and Collector Significance

• Petrology: Important for understanding vanadium mineral paragenesis in oxidized ore deposits.
• Collectors: Rare and delicate; specimens are valued academically rather than aesthetically.
• Industrial Note: No commercial use; significance lies in its rarity and unusual chemistry.

✨ Conclusion

Alvanite is a rare vanadate mineral combining Zn, Ni, Al, and V, first discovered in Kazakhstan. Its micaceous bluish-green crystals are scientifically important for vanadium mineralogy but remain a collector’s curiosity rather than an economic resource.

In short: Alvanite = rare Zn–Ni–Al vanadate, monoclinic, bluish-green, first found in Karatau Mountains, Kazakhstan.