Anatase In Quartz Gemstone & Information | Gemopedia by JTV | Gemopedia™
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.
Colorless With Orange Brown, Brown, Pale Yellow, Black, Green, Liliac, Gray Inclusions
Anatase-in-quartz classificationCommonNameAnatase In QuartzSpeciesQuartzVarietyColorsColorless With Orange Brown, Brown, Pale Yellow, Black, Green, Liliac, Gray InclusionsAlternateNamesGemstoneGroupsKeySeparationsRefractive 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.ClassificationCommentsAnatase is a polymorph of rutile and brookite.
Anatase-in-quartz chemistry & crystallographyChemicalNamesilicon dioxide (aka silica)ChemicalFormulaSiO2SynthesisCrystalSystemTrigonalChemistryClassificationSilicateNatureNaturalCrystallinityCrystallineChemistryComments
Anatase-in-quartz optical propertiesTransparencyTransparent - TranslucentDispersionStrength: weak fire Value: 0.013OpticalCommentsRefractiveIndex1.544-1.553
Tolerance:very constantBirefringence0.009OpticCharacterUniaxialOpticSignPositivePolariscopeReactionDoubly Refractive (DR)FluorescenceSWUV: Inert
Anatase-in-quartz characteristic physical propertiesHardness7CharacteristicCommentsStreakWhiteSpecificGravity2.64-2.69 Typical:2.66ToughnessGoodInclusionsAnatase in quartz will have anatase inclusions and may contain liquid, two-phase and three-phase inclusions, negative crystals, minerals, needles, rutile, iron particles.LusterVitreousStabilityGoodFractureConchoidalCleavageNone