Afghanite Gemstone & Information | Gemopedia by JTV | Gemopedia™

Afghanite

Named after Afghanistan where it was first discovered in a lapis lazuli mine in 1968, this rare and complex aluminosilicate forms blue crystals ranging from light aquamarine shades to saturated sapphire blue hues. The scarcity of gem-quality afghanite makes it a true collector's stone.

Colors

Blue, Colorless

  • Afghanite classification

    CommonName
    Afghanite
    Species
    Afghanite
    Variety
    Colors
    Blue, Colorless
    AlternateNames
    GemstoneGroups
    Cancrinite
    KeySeparations
    ClassificationComments
    Afghanite is found in the lapis lazuli mines in Afghanistan. Stones should be cleaned with distilled water.
  • Afghanite chemistry & crystallography

    ChemicalName
    hydrated sodium calcium potassium aluminum silicate carbonate
    ChemicalFormula
    (Na, Ca, K)12-(Si, Al)16O34(Cl, SO4, CO3)4.H2O
    Synthesis
    CrystalSystem
    Hexagonal
    ChemistryClassification
    Silicate
    Nature
    Natural
    Crystallinity
    Crystalline
    ChemistryComments
  • Afghanite optical properties

    Transparency
    Transparent
    Dispersion
    OpticalComments
    RefractiveIndex
    1.523-1.529
    Birefringence
    0.006
    OpticCharacter
    Uniaxial
    OpticSign
    Positive
    PolariscopeReaction
    Doubly Refractive (DR)
    Fluorescence
    SWUV: Inert
    LWUV: Inert
    CCFReaction
    Pleochroism
    None
  • Afghanite characteristic physical properties

    Hardness
    5.5-6
    CharacteristicComments
    Streak
    SpecificGravity
    2.55-2.65 Typical:2.5
    Toughness
    Poor
    Inclusions
    Stones often include lazurite inclusions.
    Luster
    Vitreous
    Stability
    Fracture
    Cleavage
    Perfect, in one direction