Cultured Pearl Gemstone & Information | Gemopedia by JTV | Gemopedia™

Cultured Pearl

Pearls are the only gems that are grown inside living creatures, so rather than being mined like other gems, pearls can be farmed and harvested. Pearls have been harvested from mollusks for thousands of years, either by chance or, more recently, purposely through culturing. From the start of mankind's love affair with pearls, they have been symbolic of class, purity, refinement, and wealth, but modern designs with fashionable new pearl shapes and colors are helping pearls appeal to a broader audience. They truly are not just your grandmother's pearls anymore.

Colors

White, Cream, Golden, Silver, Gray, Brown, Black

  • Cultured-pearl classification

    CommonName
    Cultured Pearl
    Species
    NA
    Variety
    Cultured Pearl
    Colors
    White, Cream, Golden, Silver, Gray, Brown, Black
    AlternateNames
    GemstoneGroups
    KeySeparations
    refractive index, birefringence blink, specific gravity and magnification. A "tooth test" is commonly used in which a pearl is rubbed against a tooth; if gritty, this is an indication that the surface is nacre, versus plastic and glass imitations that feel smooth.
    ClassificationComments
    Major classifications include natural/cultured and saltwater/freshwater. Major types of cultured pearls include Akoya, Tahitian, South Sea and Freshwater.
  • Cultured-pearl chemistry & crystallography

    ChemicalName
    calcium carbonate + conchiolin and water
    ChemicalFormula
    CaCO3
    Synthesis
    CrystalSystem
    NA
    ChemistryClassification
    Organic
    Nature
    Cultured
    Crystallinity
    Non-Crystalline
    ChemistryComments
  • Cultured-pearl optical properties

    Transparency
    Translucent - Opaque
    Dispersion
    OpticalComments
    RefractiveIndex
    1.53-1.685
    Birefringence
    0.155-0.155
    OpticCharacter
    NA
    OpticSign
    NA
    PolariscopeReaction
    Aggregate (AGG)
    Fluorescence
    SWUV: inert to strong light blue, yellow, green or pink
    LWUV: inert to strong light blue, yellow, green or pinknatural black: weak to moderate red to orangy red to brownish redLa Paz: strong red
    CCFReaction
    Pleochroism
    None
  • Cultured-pearl characteristic physical properties

    Hardness
    3.5-4
    CharacteristicComments
    Streak
    SpecificGravity
    2.72-2.78
    Toughness
    Fair
    Inclusions
    Cultured pearls will have an iridescent surface. If the pearl is drilled you can inspect the hole to look for bead nucleus.
    Luster
    Pearly
    Stability
    Poor
    Fracture
    Uneven
    Cleavage
    None