Diamond (HPHT-treated) Gemstone & Information | Gemopedia by JTV | Gemopedia™

Diamond (HPHT-treated)

HPHT is an acronym for a process using High Pressure and High Temperatures. In this high-tech treatment technique, diamonds are subjected to extremely high temperatures and high pressures using similar equipment to that in which diamonds are synthesized. The heat and pressure simulate conditions during a diamond's formation deep in the Earth, and can cause alterations in the diamond's crystal structure and resulting appearance, thereby improving or altering a diamonds color.

Colors

Strongly Yellowish Green, Greenish Yellow, Yellow, Brownish Yellow, Colorless

  • Diamond-hpht-treated classification

    CommonName
    Diamond (HPHT-treated)
    Species
    Diamond
    Variety
    HPHT-Treated Diamond
    Colors
    Strongly Yellowish Green, Greenish Yellow, Yellow, Brownish Yellow, Colorless
    AlternateNames
    GemstoneGroups
    KeySeparations
    polish luster, OTL RI, SR nature, magnification, positive reaction to diamond tester, advanced lab testing
    ClassificationComments
    Produced by treating brown nitrogen containing Type Ia diamonds.
  • Diamond-hpht-treated chemistry & crystallography

    ChemicalName
    carbon
    ChemicalFormula
    C
    Synthesis
    CrystalSystem
    Cubic
    ChemistryClassification
    Native Element
    Nature
    Natural
    Crystallinity
    Crystalline
    ChemistryComments
  • Diamond-hpht-treated optical properties

    Transparency
    Transparent - Translucent
    Dispersion
    Strength: moderate fire Value: 0.044
    OpticalComments
    RefractiveIndex
    2.417-0
    Birefringence
    OpticCharacter
    NA
    OpticSign
    NA
    PolariscopeReaction
    Singly Refractive (SR)
    Fluorescence
    SWUV: Variable
    LWUV: Variable
    CCFReaction
    Pleochroism
    None
  • Diamond-hpht-treated characteristic physical properties

    Hardness
    10
    CharacteristicComments
    Streak
    SpecificGravity
    3.51-3.53 Typical:3.52
    Toughness
    Good
    Inclusions
    Etched or pitted naturals or feathers, tension fractures sometimes containing graphite around crystalline inclusions.
    Luster
    Adamantine
    Stability
    Excellent
    Fracture
    Uneven
    Cleavage
    Perfect, in four directions