Dumortierite In Quartz Gemstone & Information | Gemopedia by JTV | Gemopedia™

Dumortierite In Quartz

Named for the 19th century French paleontologist Eugene Dumortier, dumortierite crystals are intensely colored and extremely scarce, making them highly prized by mineral collectors. Frequently, dumortierite grows as inclusions within quartz, occurring as an abundance of tiny blue specks, so much as to make the gem appear blue. Other dumortierite colors include pink, purple, pink, reddish brown to brown.

Colors

Dark Blue To Violet

  • Dumortierite-in-quartz classification

    CommonName
    Dumortierite In Quartz
    Species
    Quartz
    Variety
    Dumortierite In Quartz
    Colors
    Dark Blue To Violet
    AlternateNames
    Dumortierite Quartz
    GemstoneGroups
    KeySeparations
    Refractive index, appearance, birefringence, optic character and optic figure. A bull's-eye optic figure is determinative for quartz; may also show Airy's spiral optic figure and Brazil-law twinning under crossed polarizing filters.
    ClassificationComments
    Misnomer: California lapis
  • Dumortierite-in-quartz chemistry & crystallography

    ChemicalName
    silicon dioxide (aka silica)
    ChemicalFormula
    SiO2
    Synthesis
    CrystalSystem
    Trigonal
    ChemistryClassification
    Silicate
    Nature
    Natural
    Crystallinity
    Crystalline to Aggregate
    ChemistryComments
  • Dumortierite-in-quartz optical properties

    Transparency
    Translucent - Opaque
    Dispersion
    OpticalComments
    RefractiveIndex
    1.544-1.553
    Tolerance:very constant
    Birefringence
    0.009
    OpticCharacter
    Uniaxial
    OpticSign
    Positive
    PolariscopeReaction
    Doubly Refractive (DR)
    Fluorescence
    SWUV: Inert
    LWUV: Inert
    CCFReaction
    Pleochroism
    None
  • Dumortierite-in-quartz characteristic physical properties

    Hardness
    7
    CharacteristicComments
    Streak
    White
    SpecificGravity
    2.64-2.69 Typical:2.66
    Toughness
    Good
    Inclusions
    Dumortierite in quartz will contain dumortierite inclusions and might have liquid, two-phase and three-phase inclusions, negative crystals, minerals, needles, rutile and iron particles.
    Luster
    Dull
    Stability
    Good
    Fracture
    Conchoidal, Granular
    Cleavage
    None