Rutilated Quartz Gemstone & Information | Gemopedia by JTV | Gemopedia™
Gemstones are usually treasured for their crystalline varieties that contain little or no inclusions. Some varieties, however, are favored because of their unique inclusions. One such variety is rutilated quartz. Striking in appearance, the thin, elongated red to golden rutile needles may form parallel to one another or have random distribution throughout the quartz. On rare occasions, needles may radiate in six different directions, creating a star-like pattern. Specimens exhibiting this pattern are the most highly prized of all.
Colorless With Reddish, Golden, Silvery, Greenish Needles
Rutilated-quartz classificationCommonNameRutilated QuartzSpeciesQuartzVarietyRutilated QuartzColorsColorless With Reddish, Golden, Silvery, Greenish NeedlesAlternateNamesSagenitic QuartzGemstoneGroupsKeySeparationsRefractive 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.ClassificationCommentsColorless quartz with visible needle-like inclusions is sometimes called "sagenitic."
Rutilated-quartz chemistry & crystallographyChemicalNamesilicon dioxide (aka silica)ChemicalFormulaSiO2SynthesisCrystalSystemTrigonalChemistryClassificationSilicateNatureNaturalCrystallinityCrystallineChemistryComments
Rutilated-quartz optical propertiesTransparencyTransparent - OpaqueDispersionStrength: weak fire Value: 0.013OpticalCommentsRefractiveIndex1.544-1.553
Tolerance:very constantBirefringence0.009OpticCharacterUniaxialOpticSignPositivePolariscopeReactionDoubly Refractive (DR)FluorescenceSWUV: Inert
Rutilated-quartz characteristic physical propertiesHardness7CharacteristicCommentsStreakWhiteSpecificGravity2.64-2.69 Typical:2.66ToughnessGoodInclusionsRutilated quartz will have rutile inclusions and might contain liquid, two-phase and three-phase inclusions, negative crystals, minerals, needles and iron particles.LusterVitreousStabilityGoodFractureConchoidalCleavageNone