Selenite Gemstone & Information | Gemopedia by JTV | Gemopedia™

Selenite

Selenite is the name for transparent, colorless to near colorless crystals of gypsum, a hydrous calcium sulfate that is found in a number of forms. The name "selenite" comes from the Greek word selene, meaning "moon", no doubt in reference to the gem's white glow. Gypsum, in all varieties, is very soft and has perfect cleavage so it should be handled with care.

Colors

Mostly White

  • Selenite classification

    CommonName
    Selenite
    Species
    Gypsum
    Variety
    Selenite
    Colors
    Mostly White
    AlternateNames
    GemstoneGroups
    KeySeparations
    Appearance, RI and SG. Poor polished surface due to low mohs hardness.
    ClassificationComments
    Transparent colorless variety of gypsum.
  • Selenite chemistry & crystallography

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

    Transparency
    Translucent
    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 white or greenish white
    LWUV: Inert to weak brownish white or greenish white
    CCFReaction
    Pleochroism
    None
  • Selenite characteristic physical properties

    Hardness
    1.5-2
    CharacteristicComments
    Streak
    White
    SpecificGravity
    2.25-2.35 Typical:2.3
    Toughness
    Poor
    Inclusions
    Luster
    Waxy
    Stability
    Fair
    Fracture
    Granular
    Cleavage
    Perfect, in one direction, Good, in two directions