Albite

Albite is a common feldspar mineral, specifically the sodium-rich endmember of the plagioclase feldspar series. It is one of the most widespread rock-forming minerals, occurring in igneous, metamorphic, and sedimentary environments.


🌍 Origins and Naming

  • Name Origin: From Latin albus (“white”), referring to its typical color.
  • Type Locality: Described in the early 19th century, widely distributed worldwide.

🔬 Chemical and Structural Properties

  • Formula: NaAlSi₃O₈
  • Mineral Group: Feldspar (plagioclase series)
  • Crystal System: Triclinic
  • Color: White, colorless, sometimes gray, bluish, or greenish
  • Habit: Tabular crystals, granular masses, or cleavable fragments
  • Hardness: 6–6.5 on Mohs scale
  • Specific Gravity: ~2.62
  • Luster: Vitreous
  • Streak: White
  • Cleavage: Perfect on {001}, good on {010}

⚙️ Geological Occurrence

  • Igneous Rocks: Common in granites, pegmatites, rhyolites.
  • Metamorphic Rocks: Found in schists and gneisses.
  • Sedimentary Rocks: Present as detrital grains in sandstones.
  • Associated Minerals: Quartz, orthoclase, microcline, muscovite, biotite.

📖 Scientific and Economic Significance

  • Petrology: Key mineral for classifying igneous rocks (especially granites and pegmatites).
  • Industrial Use:
    • Source of sodium in ceramics and glass manufacture.
    • Used in porcelain production.
  • Collectors: Transparent crystals from pegmatites can be attractive, though albite is usually common and not highly prized.

✨ Conclusion

Albite is a sodium-rich feldspar (NaAlSi₃O₈), widespread in igneous and metamorphic rocks, important in geology and industry. While common, it plays a crucial role in rock classification and has practical applications in ceramics and glass.


In short: Albite = sodium feldspar, triclinic, white to colorless, abundant in granites and pegmatites.

 

Author: j5rson

Chief curmudgeon.

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