Liddicoatite Gemstone & Information | Gemopedia by JTV | Gemopedia™

Liddicoatite

Liddicoatite is a calcium-rich lithium species of tourmaline named in 1977 in honor of noted gemologist Richard T. Liddicoat. Gems may form in green, pink, red, blue and purple colors, sometimes with internal multicolor banding and zoning. Large crystals are often sliced to display their natural multicolor designs.

Colors

Green, Red, Pink, Purple, Blue, Colorless, Black, Brown, Yellow, Orange, Frequently Multi-Colored

  • Liddicoatite classification

    CommonName
    Liddicoatite
    Species
    Liddicoatite
    Variety
    Colors
    Green, Red, Pink, Purple, Blue, Colorless, Black, Brown, Yellow, Orange, Frequently Multi-Colored
    AlternateNames
    Fluor-Liddicoatite
    GemstoneGroups
    Tourmaline
    KeySeparations
    appearance, refractive index and high birefringence; then optic figure, pleochroism and specific gravity
    ClassificationComments
    Name after Richard T. Liddicoat pioneering gemologist at GIA
  • Liddicoatite chemistry & crystallography

    ChemicalName
    calcium lithium aluminum bora-silicate hydroxide
    ChemicalFormula
    Ca(Li2Al)Al6(Si6O18)(BO3)3(OH)3(OH)
    Synthesis
    CrystalSystem
    Trigonal
    ChemistryClassification
    Silicate
    Nature
    Natural
    Crystallinity
    Crystalline
    ChemistryComments
  • Liddicoatite optical properties

    Transparency
    Transparent - Translucent
    Dispersion
    Strength: weak fire Value: 0.017
    OpticalComments
    RefractiveIndex
    1.624
    Tolerance:-1.22222222222222
    Birefringence
    0.018-0.02
    OpticCharacter
    Uniaxial
    OpticSign
    Negative
    PolariscopeReaction
    Doubly Refractive (DR)
    Fluorescence
    SWUV: Inert
    LWUV: Inert
    CCFReaction
    Pleochroism
    Dichroic, moderate to strong, varying shades of body color
  • Liddicoatite characteristic physical properties

    Hardness
    7.5
    CharacteristicComments
    Streak
    Light Brown, White
    SpecificGravity
    Typical:3.02
    Toughness
    Good
    Inclusions
    Liddicoatite is a type II clarity stone. Stones might contain liquid and gas inclusions that are long and thin, reflective gas-filled fractures and color zoning.
    Luster
    Vitreous
    Stability
    Very Good
    Fracture
    Conchoidal, Uneven
    Cleavage
    Poor, in two directions