Ammolite Doublets Or Triplets Gemstone & Information | Gemopedia by JTV | Gemopedia™

Ammolite Doublets Or Triplets

Ammolite is a gem that comes from the fossilized shell of an extinct, squid-like creature called an ammonite. Found in Canada, the iridescent shell of fossilized ammonites is available as ammonite fossils or in iridescent gems cut from the fossils under the trade name ammolite. Ammolite's iridescent play of color is what makes it so distinctive and attractive. Its iridescence occurs when the fossilized ammonite shell becomes mineralized. Unlike most gems, whose colors come from light absorption, ammolite's iridescent color is caused by interference with the light that gets trapped within stacked layers of thin platelets that make up the fossilized shell. Since the layer of ammolite is typically thin, most ammolite is made into doublets or triplets for use in jewelry. A doublet is a thin slice of shell that is typically covered by a durable material (often crystal, glass or plastic) that both protect the gem and maximize its presentation. Triplets are typically assembled by placing a thin slice of shell between two layers of more durable material that are attached with epoxy. While shades of green and red are usually seen, all spectral colors are possible.

Colors

Gray To Brown With Iridescent Colors

  • Ammolite-doublets-or-triplets classification

    CommonName
    Ammolite Doublets Or Triplets
    Species
    NA
    Variety
    Colors
    Gray To Brown With Iridescent Colors
    AlternateNames
    Ammonite, Lumachelle, Calcentine
    GemstoneGroups
    KeySeparations
    Appearance, RI
    ClassificationComments
    Fossilized shell of nautilus like creature. Ammolite or calcentine material is from Alberta, Canada.
  • Ammolite-doublets-or-triplets chemistry & crystallography

    ChemicalName
    mostly composed of aragonite or calcite
    ChemicalFormula
    fossilized, mineralized ammonite shell
    Synthesis
    CrystalSystem
    NA
    ChemistryClassification
    Organic
    Nature
    Natural
    Crystallinity
    ChemistryComments
  • Ammolite-doublets-or-triplets optical properties

    Transparency
    Opaque
    Dispersion
    Strength: none
    OpticalComments
    RefractiveIndex
    1.52-1.68
    Tolerance:varies
    Birefringence
    0.155
    OpticCharacter
    NA
    OpticSign
    NA
    PolariscopeReaction
    Aggregate (AGG)
    Fluorescence
    SWUV: Inert to strong yellow
    LWUV: Inert to strong yellow
    CCFReaction
    Pleochroism
    None
  • Ammolite-doublets-or-triplets characteristic physical properties

    Hardness
    4
    CharacteristicComments
    Streak
    SpecificGravity
    2.7-2.8 Typical:2.7
    Toughness
    Varies
    Inclusions
    Ammolite or ammonite can be iridescent with mosaic patterns. Due to the nature of the material it is often stabilized with polymers. Well preserved specimens show a nautilus or spiral like appearance. Ammolite is often made into doublets or triplets. Quartz or lab created spinel is used as a dome and the base is typically made of shale, glass or lab created spinel.
    Luster
    Vitreous
    Stability
    Fracture
    Granular, Uneven
    Cleavage
    None