Diamond (Synthetic - HPHT) Gemstone & Information | Gemopedia by JTV | Gemopedia™
High pressure, high temperature synthetic diamonds (HPHT diamonds) are produced in a way similar to synthetic flux grown gems, however, during the HPHT process, as the name implies, the growth chamber is exposed to high temperature and pressure. The diamonds then crystallize in a lower temperature section of the growth chamber. Colored diamonds can be produced in this way. 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.
Colorless, Near Colorless, Very Light Blue, Blue To Grayish Blue, Light Gray, Green, Light Toned Pink, Dark Red, Pink To Orangy, Brownish Pink To Purplish Pink, Yellowish Green To Green To Bluish Green, Light To Dark Brownish Orange To Yellow
Diamond-synthetic-hpht classificationCommonNameDiamond (Synthetic - HPHT)SpeciesDiamondVarietyHPHT Synthetic DiamondColorsColorless, Near Colorless, Very Light Blue, Blue To Grayish Blue, Light Gray, Green, Light Toned Pink, Dark Red, Pink To Orangy, Brownish Pink To Purplish Pink, Yellowish Green To Green To Bluish Green, Light To Dark Brownish Orange To YellowAlternateNamesGemstoneGroupsKeySeparationspolish luster, OTL RI, SR nature, magnification, positive reaction to diamond tester, cross shaped, square or hour glass shaped fluorescence patterns and advanced lab testing. ADR might be in cross shaped pattern.ClassificationCommentsHPHT=high pressure, high temperature Type IIb blue, colorless, yellow or green stones might be magnetic due to metallic inclusions.
Diamond-synthetic-hpht chemistry & crystallographyChemicalNamecarbonChemicalFormulaCSynthesisHPHTCrystalSystemCubicChemistryClassificationNatureSyntheticCrystallinityCrystallineChemistryComments
Diamond-synthetic-hpht optical propertiesTransparencyTransparent - TranslucentDispersionStrength: moderate fire Value: 0.044OpticalCommentsRefractiveIndexOver the Limit 2.417-2.417BirefringenceOpticCharacterNAOpticSignNAPolariscopeReactionSingly Refractive (SR) With ADRFluorescenceSWUV: Variable
Diamond-synthetic-hpht characteristic physical propertiesHardness10CharacteristicCommentsStreakSpecificGravity3.51-3.53 Typical:3.52ToughnessGoodInclusionsElongated or rounded opaque highly reflective inclusions of metallic flux that rarely might cause the stone to be slightly magnetic. There might be clouds and pinpoints of flux in Chatham blue material. There might be impurities that might show faint color zoning in cross-shaped or hourglass pattern. Darker red stones typically will show areas of color zoning with intersecting square or cross shaped yellow areas encompassed by red. Pink stones have pink and colorless zones and might show metallic inclusions with brown halos. Irradiated green stones might have even coloration.LusterAdamantineStabilityExcellentFractureUnevenCleavagePerfect, in four directions