Smoky Quartz Gemstone & Information | Gemopedia by JTV | Gemopedia™

Smoky Quartz

Smoky quartz is an earth-toned transparent quartz that comes in a variety of shades, including cognac. Smoky quartz gets its rich warm colors from color centers related to aluminum. A popular ornamental stone, it is often carved into figurines and ornate statues, but makes quite a statement when faceted into stunning gemstones.

Colors

Brown, Beige, Pale Tan, Reddish Brown, Gray, Dark Brown Almost Black

  • Smoky-quartz classification

    CommonName
    Smoky Quartz
    Species
    Quartz
    Variety
    Smoky Quartz
    Colors
    Brown, Beige, Pale Tan, Reddish Brown, Gray, Dark Brown Almost Black
    AlternateNames
    Cairngorm If Dark Brown Or Morion If Nearly Opaque Black, Mandiore Dorado Quartz(TM), Champagne Quartz, Latte Quartz, Whiskey Quartz
    GemstoneGroups
    KeySeparations
    refractive index, birefringence, optic character and optic figure. Careful observation that reveals Brazil-law twinning separates citrine from scapolite with similar properties.
    ClassificationComments
    Smoky quartz is the common variety name for transparent quartz with a predominantly brown color with low color saturation. The brown color is due to irradiation and it can be natural or induced by by man. Misnomers: smoky topaz, burnt topaz, Scotch topaz.
  • Smoky-quartz chemistry & crystallography

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

    Transparency
    Transparent
    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
    Dichroic, unobservable or weak, varying shades of body color
  • Smoky-quartz characteristic physical properties

    Hardness
    7
    CharacteristicComments
    Streak
    White
    SpecificGravity
    2.64-2.69 Range:0.03/-0.02 Typical:2.66
    Toughness
    Good
    Inclusions
    Smoky quartz is a type II clarity stone. Color zoning often present in stones in the form of "tiger stripes" or "zebra stripes". Stones may contain crystals, negative crystals, liquid inclusions, two-phase inclusions and partially-healed fractures.
    Luster
    Vitreous
    Stability
    Good
    Fracture
    Conchoidal
    Cleavage
    None