Ruby (Synthetic Star - Czochralski) Gemstone & Information | Gemopedia by JTV | Gemopedia™

Ruby (Synthetic Star - Czochralski)

Synthetic star ruby exhibits the optical phenomenon called asterism, a star-like pattern created on the surface of a gemstone when light encounters parallel fibrous, or needle-like, inclusions within its crystal structure. Light that strikes the inclusions within the gem reflects off of the inclusions, creating a narrow band of light. When two or more intersecting bands appear, a star pattern is formed. The Czochralski process of gem synthesis involves the melting of various elements in a platinum crucible. A small gem crystal (called a seed) attached to a rod is then dipped into the melt and slowly pulled away as the crystal grows around the seed. For this reason, the Czochralski method is also known as crystal pulling. 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

Light To Dark Red, Purple Red

  • Ruby-synthetic-star-czochralski classification

    CommonName
    Ruby (Synthetic Star - Czochralski)
    Species
    Corundum
    Variety
    Pulled Synthetic Star Ruby
    Colors
    Light To Dark Red, Purple Red
    AlternateNames
    Lab Created Star Ruby
    GemstoneGroups
    KeySeparations
    Magnification, RI and maybe fluorescence
    ClassificationComments
    Stones typically have flat bases and are well cut calibrated cabochons. Stones will have brighter colors than natural rubies.
  • Ruby-synthetic-star-czochralski chemistry & crystallography

    ChemicalName
    aluminum oxide
    ChemicalFormula
    Al2O3
    Synthesis
    Czochralski pulled
    CrystalSystem
    Trigonal
    ChemistryClassification
    Oxide
    Nature
    Synthetic
    Crystallinity
    Crystalline
    ChemistryComments
  • Ruby-synthetic-star-czochralski optical properties

    Transparency
    Semitransparent - Opaque
    Dispersion
    OpticalComments
    RefractiveIndex
    1.762-1.77
    Tolerance:(+0.009/-0.005)
    Birefringence
    0.008-0.01
    OpticCharacter
    Uniaxial
    OpticSign
    Negative
    PolariscopeReaction
    Doubly Refractive (DR)
    Fluorescence
    SWUV: strong red
    LWUV: strong red
    CCFReaction
    Pleochroism
    Unobservable
  • Ruby-synthetic-star-czochralski characteristic physical properties

    Hardness
    9
    CharacteristicComments
    Streak
    White
    SpecificGravity
    4.1-3.95 Typical:4
    Toughness
    Excellent
    Inclusions
    Pulled synthetic star ruby will have extremely fine needles that produce a slightly wavy natural looking 6-rayed star. The stones typically show low-relief curved striae or wavy growth. Sometimes bluish white smoke-like swirls and small round or distorted blackish gas bubbles are seen in stones.
    Luster
    SubAdamantine
    Stability
    Very Good
    Fracture
    Conchoidal
    Cleavage
    None