Alexandrite (Synthetic) Gemstone & Information | Gemopedia by JTV | Gemopedia™

Alexandrite (Synthetic)

Some gems, like alexandrite, are almost impossible to find in nature today, much less in the sizes and quality people dream of owning. Synthetic alexandrite can be created in a variety of ways including flux growth, Czochralski method, or floating zone method. Synthetic gems have the same chemical, optical, and physical properties of their natural counterparts, but are a more cost-effective alternative to a natural gem.

Colors

Bluish Green In Daylight, Fluorescent Light, Brownish Red To Purple-Red In Incandescent

  • Alexandrite-synthetic classification

    CommonName
    Alexandrite (Synthetic)
    Species
    Chrysoberyl
    Variety
    Synthetic Alexandrite
    Colors
    Bluish Green In Daylight, Fluorescent Light, Brownish Red To Purple-Red In Incandescent
    AlternateNames
    GemstoneGroups
    KeySeparations
    Color change, refractive index, birefringence, pleochroism and spectrum help identify alexandrite, but magnification is important to distinguish synthetic from natural. Natural material might show stepped twin planes, feathers and elongated tubes or needles. Strong red fluorescence is a key indicator of synthetic.
    ClassificationComments
    Alexandrite's spectrum varies by direction, showing a different spectrum in the green direction than in the purple-red pleochroic direction. Cat's-eye synthetic alexandrite is also produced.
  • Alexandrite-synthetic chemistry & crystallography

    ChemicalName
    beryllium aluminum oxide
    ChemicalFormula
    BeAl2O4
    Synthesis
    flux growth, pulled or floating zone
    CrystalSystem
    Orthorhombic
    ChemistryClassification
    Oxide
    Nature
    Synthetic
    Crystallinity
    Crystalline
    ChemistryComments
  • Alexandrite-synthetic optical properties

    Transparency
    Transparent - Translucent
    Dispersion
    Strength: weak fire Value: 0.015
    OpticalComments
    RefractiveIndex
    1.746-1.755
    Tolerance:(+0.004/-0.006)
    Birefringence
    0.008-0.01
    OpticCharacter
    Biaxial
    OpticSign
    Positive
    PolariscopeReaction
    Doubly Refractive (DR)
    Fluorescence
    SWUV: Moderate to strong red
    LWUV: Moderate to strong red
    CCFReaction
    NA
    Pleochroism
    Trichroic, strong green, orange, and purplish red
  • Alexandrite-synthetic characteristic physical properties

    Hardness
    8.5
    CharacteristicComments
    Streak
    White
    SpecificGravity
    3.71-3.75 Range:+/- 0.02 Typical:3.73
    Toughness
    Varies
    Inclusions
    Flux grown synthetic alexandrite might have metallic platelets from the platinum crucible, veil like inclusions, flux inclusions, flux filled cavities, straight or angular growth lines layers of dust-like inclusions parallel to seed plate.Czochralski method pulled stones will have needle like inclusions, curved striae and small black like gas bubbles.Floating zone or hydrothermal stones will have dark gas bubbles, long flat liquid inclusion and a swirled appearance.
    Luster
    Bright Vitreous
    Stability
    Very Good
    Fracture
    Conchoidal
    Cleavage
    Good, in one direction