Actinolite (Cat's-Eye) Gemstone & Information | Gemopedia by JTV | Gemopedia™

Actinolite (Cat's-Eye)

The term cat's eye, or chatoyancy, is used to describe a phenomenal optical property in gemstones, in this case actinolite. The effect, when present, appears as a bright, narrow slit similar to the pupils in the eyes of your favorite feline. This phenomenon is caused by parallel fibrous or needle-like inclusions that interfere with the passage of light throughout the crystal, scattering and reflecting light back to the viewer as a thin line.

Colors

Yellowish Green, Light To Dark Green, Black

  • Actinolite-cats-eye classification

    CommonName
    Actinolite (Cat's-Eye)
    Species
    Actinolite
    Variety
    Cat's-Eye Actinolite
    Colors
    Yellowish Green, Light To Dark Green, Black
    AlternateNames
    GemstoneGroups
    Amphibole
    KeySeparations
    Appearance, poor surface quality, RI and SG
    ClassificationComments
    Actinolite usually fibrous aggregate. Misnomer jade cat's-eye.
  • Actinolite-cats-eye chemistry & crystallography

    ChemicalName
    calcium magnesium iron silicate hydroxide
    ChemicalFormula
    Ca2(Mg, Fe)5Si8O22(OH)2
    Synthesis
    CrystalSystem
    Monoclinic
    ChemistryClassification
    Silicate
    Nature
    Natural
    Crystallinity
    Crystalline to Aggregate
    ChemistryComments
  • Actinolite-cats-eye optical properties

    Transparency
    Semitransparent - Opaque
    Dispersion
    Strength: none
    OpticalComments
    RefractiveIndex
    1.614-1.641
    Tolerance:0.014
    Birefringence
    0.022-0.027
    OpticCharacter
    Biaxial
    OpticSign
    Positive
    PolariscopeReaction
    Aggregate (AGG)
    Fluorescence
    SWUV: Inert
    LWUV: Inert
    CCFReaction
    Pleochroism
    Dichroic, moderate yellow and dark green
  • Actinolite-cats-eye characteristic physical properties

    Hardness
    5-6
    CharacteristicComments
    Streak
    White
    SpecificGravity
    2.95-3.1 Typical:3
    Toughness
    Excellent
    Inclusions
    It is the fibrous structure that causes chatoyancy.
    Luster
    Vitreous
    Stability
    Good
    Fracture
    Uneven
    Cleavage
    Perfect, in two directions