Mineraller ve özellikleri Albit General Albite Information Chemical Formula: NaAlSi3O8 Composition: Molecular Weight = 263.02 gm Sodium 8.30 % Na 11.19 % Na 2 O Calcium 0.76 % Ca 1.07 % CaO Aluminum 10.77 % Al 20.35 % Al 2 O 3 Silicon 31.50 % Si 67.39 % SiO 2 Oxygen 48.66 % O ______ ______ 100.00 % 100.00 % = TOTAL OXIDE Empirical Formula: Na0.95Ca0.05Al 1.05Si2.95O 8 Environment: Magmatic and pegmatitic rocks. Name Origin: From the Latin, albus, in allusion to the common color. Synonym: Ab100 An0 Clevelandite Albite Crystallography Axial Ratios: a:b:c =0.6368:1:0.5599 Cell Dimensions: a = 8.144, b = 12.787, c = 7.16, Z = 4; alpha = 94.266°, beta = 116.583°, gamma = 87.667° V = 664.40 Den(Calc)= 2.63 Crystal System: Triclinic - PinacoidalH-M Symbol ( 1) Space Group: C1 X Ray Diffraction: By Intensity(I/I o): 3.176(1), 3.211(0.3), 3.752(0.3), Forms: [ 0 0 1] [ 1 0 0] [ 1 0 1] [ 0 1 0] Physical Properties of Albite Cleavage: [001] Perfect, [010] Good Color: White, Gray, Greenish gray, Bluish green, Gray. Density: 2.61 - 2.63, Average = 2.62 Diaphaniety: Transparent to translucent to subtranslucent Fracture: Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern. Habits: Blocky - Crystal shape tends to be equant (e.g. feldspars)., Striated - Parallel lines on crystal surface or cleavage face., Granular - Generally occurs as anhedral to subhedral cryst als in matrix. Hardness: 7 - Quartz Luminescence: None. Luster: Vitreous (Glassy) Streak: white Optical Properties of Albite Optical Data: Biaxial (+), a=1.528-1.533, b=1.5317-1.53685, g=1.538-1.542, bire=0.0090-0.0100, 2V(Calc)=76-82, 2V(Meas)=45. Dispersion relatively weak.