Alabaster Gemstone & Information | Gemopedia by JTV | Gemopedia™

Alabaster

Alabaster is a fine grained massive form of gypsum. Alabaster ranges from white to yellow, green and brown, but because of its porosity, it is often dyed a snow white color which resembles marble. It has been used for centuries for statues, carvings and other ornamental purposes. Due to its extreme softness, it is ideal for fashioning into works of art.

Colors

White, Gray, Pink, Reddish, Greenish, Yellow, Brown, Black Veins, Color Concentrations

  • Alabaster classification

    CommonName
    Alabaster
    Species
    Gypsum
    Variety
    Alabaster
    Colors
    White, Gray, Pink, Reddish, Greenish, Yellow, Brown, Black Veins, Color Concentrations
    AlternateNames
    Alabastrite
    GemstoneGroups
    KeySeparations
    Appearance, RI and SG. Poor polished surface due to low mohs hardness.
    ClassificationComments
  • Alabaster chemistry & crystallography

    ChemicalName
    hydrous calcium sulfate
    ChemicalFormula
    CaSO4-2H2O
    Synthesis
    CrystalSystem
    Monoclinic
    ChemistryClassification
    Sulfate
    Nature
    Natural
    Crystallinity
    Crystalline
    ChemistryComments
  • Alabaster optical properties

    Transparency
    Translucent - Opaque
    Dispersion
    OpticalComments
    RefractiveIndex
    1.52-1.529
    Tolerance:(+0.001/-0.001)
    Birefringence
    0.009-0.01
    OpticCharacter
    Biaxial
    OpticSign
    Positive
    PolariscopeReaction
    Doubly Refractive (DR)
    Fluorescence
    SWUV: Inert to weak brownish to greenish white
    LWUV: Inert to weak brownish to greenish white
    CCFReaction
    Pleochroism
    None
  • Alabaster characteristic physical properties

    Hardness
    1.5-2
    CharacteristicComments
    Streak
    White
    SpecificGravity
    2.25-2.35 Typical:2.3
    Toughness
    Poor
    Inclusions
    Alabaster is sometimes banded, veined,or patterned like marble and it is often dyed and has a poor polish.
    Luster
    Waxy
    Stability
    Fair
    Fracture
    Granular
    Cleavage
    None