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

Anatase In Quartz

Anatase is a relatively uncommon gemmy form of titanium dioxide that forms very small unique crystals. The name anatase comes from a Greek word meaning "elongation," referencing its elongated crystal form. Anatase is a polymorph to the more common rutile, as well as brookite. We sometimes see long rutile needles shooting through gemstones, but small anatase crystal inclusions is a much rarer occurrence. Like rutile, anatase usually occurs in honey-yellow, brown to reddish brown, black or deep blue colors.

Colors

Colorless With Orange Brown, Brown, Pale Yellow, Black, Green, Liliac, Gray Inclusions

  • Anatase-in-quartz classification

    CommonName
    Anatase In Quartz
    Species
    Quartz
    Variety
    Colors
    Colorless With Orange Brown, Brown, Pale Yellow, Black, Green, Liliac, Gray Inclusions
    AlternateNames
    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
    Anatase is a polymorph of rutile and brookite.
  • Anatase-in-quartz chemistry & crystallography

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

    Transparency
    Transparent - Translucent
    Dispersion
    Strength: weak fire Value: 0.013
    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
  • Anatase-in-quartz characteristic physical properties

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