Cavansite Gemstone & Information | Gemopedia by JTV | Gemopedia™

Cavansite

Very distinctive in appearance, cavansite is a rare, not to mention strikingly beautiful, blue mineral. Its name is derived from its composition: calcium, vanadium and silicon. Only discovered in the 1960's in Oregon, cavansite is highly sought after by mineral collectors across the globe. Found in a scant few locales, cavansite sources include Brazil, India, New Zealand and Oregon USA. It is renowned for its stunning deep blue hues that are sometimes vivid enough to be described as "electric blue."

Colors

Greenish Blue To Blue

  • Cavansite classification

    CommonName
    Cavansite
    Species
    Cavansite
    Variety
    Colors
    Greenish Blue To Blue
    AlternateNames
    GemstoneGroups
    KeySeparations
    Optic character, appearance and pleochroism.
    ClassificationComments
  • Cavansite chemistry & crystallography

    ChemicalName
    hydrated calcium vanadium silicate
    ChemicalFormula
    Ca(VO)Si4O10.4H2O
    Synthesis
    CrystalSystem
    Orthorhombic
    ChemistryClassification
    Silicate
    Nature
    Natural
    Crystallinity
    Crystalline
    ChemistryComments
  • Cavansite optical properties

    Transparency
    Transparent
    Dispersion
    Strength: weak fire
    OpticalComments
    RefractiveIndex
    1.542-1.551
    Birefringence
    0.009
    OpticCharacter
    Biaxial
    OpticSign
    Positive
    PolariscopeReaction
    Doubly Refractive (DR)
    Fluorescence
    SWUV: Inert
    LWUV: Inert
    CCFReaction
    Pleochroism
    Dichroic, strong colorless and blue
  • Cavansite characteristic physical properties

    Hardness
    3-4
    CharacteristicComments
    Streak
    SpecificGravity
    2.21-2.31
    Toughness
    Poor
    Inclusions
    Luster
    Vitreous
    Stability
    Fracture
    Conchoidal
    Cleavage
    Good, in one direction