Forsterite (Synthetic) Gemstone & Information | Gemopedia by JTV | Gemopedia™
Synthetic forsterite (a variety of olivine) is produced by a process called the Czochralski method. Material containing the elements that make up the mineral forsterite (magnesium, silicon, and oxygen) are melted in a platinum crucible. A small forsterite crystal (called a seed) that is attached to a rod is then dipped into the melt and slowly pulled away as the crystal grows around the seed. For this reason, the Czochralski method is also known as crystal pulling. Synthetic gems have the same chemical, optical, and physical properties of their natural counterparts, but are a more cost-effective alternative to a natural gem.
Violet To Bluish Violet
Forsterite-synthetic classificationCommonNameForsterite (Synthetic)SpeciesForsteriteVarietyColorsViolet To Bluish VioletAlternateNamesGemstoneGroupsOlivineKeySeparationsRI, birefringence and possible pleochroismClassificationCommentsSynthetic forsterite is often sold as a tanzanite simulant.
Forsterite-synthetic chemistry & crystallographyChemicalNamemagnesium silicateChemicalFormulaMg2SiO4SynthesisCzochralski pulledCrystalSystemOrthorhombicChemistryClassificationSilicateNatureSyntheticCrystallinityCrystallineChemistryComments
Forsterite-synthetic optical propertiesTransparencyTransparentDispersionOpticalCommentsRefractiveIndex1.635-1.67Birefringence0.034-0.035OpticCharacterBiaxialOpticSignPositivePolariscopeReactionDoubly Refractive (DR)FluorescenceSWUV: Weak greenish yellow
LWUV: Weak chalky orangy yellowCCFReactionPleochroismDichroic, strong blue and purplish pink
Forsterite-synthetic characteristic physical propertiesHardness6.5-7CharacteristicCommentsStreakWhiteSpecificGravity3.23-3.24 Typical:3.23ToughnessInclusionsSynthetic forsterite sometimes includes gas bubbles, tiny white specks, minute needlesLusterVitreousStabilityFractureConchoidalCleavageGood, in two directions