Smoky Quartz Gemstone & Information | Gemopedia by JTV | Gemopedia™
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.
Brown, Beige, Pale Tan, Reddish Brown, Gray, Dark Brown Almost Black
Smoky-quartz classificationCommonNameSmoky QuartzSpeciesQuartzVarietySmoky QuartzColorsBrown, Beige, Pale Tan, Reddish Brown, Gray, Dark Brown Almost BlackAlternateNamesCairngorm If Dark Brown Or Morion If Nearly Opaque Black, Mandiore Dorado Quartz(TM), Champagne Quartz, Latte Quartz, Whiskey QuartzGemstoneGroupsKeySeparationsrefractive index, birefringence, optic character and optic figure. Careful observation that reveals Brazil-law twinning separates citrine from scapolite with similar properties.ClassificationCommentsSmoky 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 & crystallographyChemicalNamesilicon dioxide (aka silica)ChemicalFormulaSiO2SynthesisCrystalSystemTrigonalChemistryClassificationSilicateNatureNaturalCrystallinityCrystallineChemistryComments
Smoky-quartz optical propertiesTransparencyTransparentDispersionStrength: weak fire Value: 0.013OpticalCommentsRefractiveIndex1.544-1.553
Tolerance:very constantBirefringence0.009OpticCharacterUniaxialOpticSignPositivePolariscopeReactionDoubly Refractive (DR)FluorescenceSWUV: Inert
LWUV: InertCCFReactionPleochroismDichroic, unobservable or weak, varying shades of body color
Smoky-quartz characteristic physical propertiesHardness7CharacteristicCommentsStreakWhiteSpecificGravity2.64-2.69 Range:0.03/-0.02 Typical:2.66ToughnessGoodInclusionsSmoky 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.LusterVitreousStabilityGoodFractureConchoidalCleavageNone