Ivory Gemstone & Information | Gemopedia by JTV | Gemopedia™

Ivory

Ivory has long been treasured for its beautiful white color and ability to be finely carved. As opposed to bone or horn, ivory is derived from the teeth and tusks of animals. Because of the devastating impact of poaching due to the ivory trade, the importation and sale of such materials is severely restricted or banned in many countries.

Colors

White To Light Yellow

  • Ivory classification

    CommonName
    Ivory
    Species
    Ivory
    Variety
    Colors
    White To Light Yellow
    AlternateNames
    GemstoneGroups
    KeySeparations
    RI, magnification, SG and possible fluorescence
    ClassificationComments
    The trade on new elephant ivory has been banned sine 1991.Mammoth or mastodon ivory can have a hardness up to 5 and an SG up to 3.00. Walrus ivory can only be processed and sold by the Inuit of North America and Greenland.Currently the Canadian Department of Fisheries and Oceans restricts the export of narwhal tusks but the Inuit traders are challenging the ban in court. The United States restricts the import of walrus and narwal ivory. More information about the ivory ban can be found at http://www.cites.org/.
  • Ivory chemistry & crystallography

    ChemicalName
    calcium hydroxyl phosphate
    ChemicalFormula
    Dentine from teeth or modified teeth of mammals such as elephant, mammoth, hippopotamus, warthog, narwal or walrus
    Synthesis
    CrystalSystem
    NA
    ChemistryClassification
    Organic
    Nature
    Natural
    Crystallinity
    Amorphous
    ChemistryComments
  • Ivory optical properties

    Transparency
    Translucent - Opaque
    Dispersion
    OpticalComments
    RefractiveIndex
    1.535-1.54
    Birefringence
    OpticCharacter
    OpticSign
    PolariscopeReaction
    Aggregate (AGG)
    Fluorescence
    SWUV: weak to moderate bluish white or violet blue
    LWUV: weak to strong bluish white or violet blue
    CCFReaction
    Pleochroism
    None
  • Ivory characteristic physical properties

    Hardness
    2.2-2.8
    CharacteristicComments
    Streak
    White
    SpecificGravity
    1.7-2
    Toughness
    Fair
    Inclusions
    Elephant and mammoth ivory will have wavy or intersecting curved lines in a v shaped pattern called engine turning effect. Mammoth or Moscow ivory tends to have more cracks than modern ivory. Walrus ivory or sea ivory is oval in cross section and the center has a rough bumpy appearance. Whale ivory comes from the teeth of sperm whales and can be found in antique Inuit carvings and scrimshaw. Narwhal ivory is hollow in the middle and tree-ring like growth patterns and a right to left spiral pattern.
    Luster
    Greasy
    Stability
    Fracture
    Splintery
    Cleavage
    None