Albite – [NaAlSi3O8]

Albite, member of the feldspar group, is one of the most common minerals. It occurs as sharp, well-formed, bladed crystals from millimeter size to several centimeters in length, as well as in fine rhodochrosite, elpidite and other minerals. The pink color tends to fade somewhat after extended periods of natural light.

PHYSICAL CHARACTERISTICS:

 

  • Color is colorless, white and rarely pink.
  • Luster is vitreous.
  • Diaphaneity varies from transparent to opaque.
  • Crystal System is triclinic; C1 or P1.
  • Crystal Habits include tabular to platy crystals.
  • Cleavage {001} is perfect and {010} is good.
  • Fracture is uneven to subconchoidal.
  • Hardness is 6 – 6.5
  • Specific Gravity is approximately 2.6 g/cm3
  • Streak is white.
  • Associated Minerals include many minerals with the most common
    being: aegirine, pyrite, pyrrhotite, rhodochrosite, siderite and
    synchysite.
  • Distinguishing Features: Crystal habit.
  • Origin: Named in 1815 from Greek albus, white, alluding to its usual
    color.

 

 

Dana class # 76.1.3.1 – Tectosilicates; Al – Si framework;
feldspar group, plagioclase subgroup
Strunz class # VIII/J.7-20 – Silicates; tectosilicates (network) without anions unfamiliar to the tetraheders; feldspar group, anorthoclase – anorthite – banalcite series