Oregon Sunstone Gemstone & Information | Gemopedia by JTV | Gemopedia™

Oregon Sunstone

While feldspars are found throughout the world, they are rarely of gem quality. However, there is a very special feldspar variety known as sunstone found in south central Oregon. The Oregon sunstone is both gem grade and available in large enough sizes to yield cut stones for jewelry. The deposit is located in the region's rugged high desert where sunstone is embedded in ancient lava flows of an extinct volcano. As the lava weathers away or is broken up, Mother Nature releases the crystals for man to gather.

Colors

Pale Pinkish Orange, Pink, Reddish Orange, Red-Orange, Deep Red With Red, Green, Blue Adventurescence

  • Oregon-sunstone classification

    CommonName
    Oregon Sunstone
    Species
    Labradorite
    Variety
    Oregon Sunstone
    Colors
    Pale Pinkish Orange, Pink, Reddish Orange, Red-Orange, Deep Red With Red, Green, Blue Adventurescence
    AlternateNames
    Aventurine Feldspar
    GemstoneGroups
    Feldspar
    KeySeparations
    RI, birefringence, optic character and magnification.
    ClassificationComments
  • Oregon-sunstone chemistry & crystallography

    ChemicalName
    potassium, sodium or calcium silicate
    ChemicalFormula
    NaAlSi3O8 or CaAl2SiO8
    Synthesis
    CrystalSystem
    Triclinic
    ChemistryClassification
    Silicate
    Nature
    Natural
    Crystallinity
    Crystalline
    ChemistryComments
  • Oregon-sunstone optical properties

    Transparency
    Translucent - Opaque
    Dispersion
    Strength: none
    OpticalComments
    RefractiveIndex
    1.563-1.572
    Birefringence
    0.009
    OpticCharacter
    Biaxial
    OpticSign
    Positive
    PolariscopeReaction
    Doubly Refractive (DR)
    Fluorescence
    SWUV: Inert to moderate red
    LWUV: Inert to moderate violet
    CCFReaction
    Pleochroism
    Dichroic, strong red and green
  • Oregon-sunstone characteristic physical properties

    Hardness
    6
    CharacteristicComments
    Streak
    White
    SpecificGravity
    2.67-2.72 Typical:2.67
    Toughness
    Poor
    Inclusions
    Oregon sunstone contain tiny orange or yellow copper platelets or hematite platelets and stones might display adventurescence. Parting is common in this material.
    Luster
    Vitreous
    Stability
    Good
    Fracture
    Uneven, Splintery
    Cleavage
    Perfect, in two directions