Tortoise Shell Gemstone & Information | Gemopedia by JTV | Gemopedia™
Tortoise shell used in ornamentation traditionally comes from the shell of the hawksbill sea turtle. The multicolored marbled patterns of the shell are coveted not only for their unique colorations, but also their deep translucence. When heated, the shell becomes soft and can be molded into jewelry and other decorated articles. Due to the depletion of the species today, its use is illegal in many countries and has primarily been replaced by synthetic tortoise shell.
Mottled Yellow, Brown, Sometimes Black, White
Tortoise-shell classificationCommonNameTortoise ShellSpeciesNAVarietyColorsMottled Yellow, Brown, Sometimes Black, WhiteAlternateNamesGemstoneGroupsKeySeparationsAppearance, RI and magnification. Will smell like burning hair during hot point test.ClassificationCommentsHawksbill turtles are an endangered species and importation of tortoise shell is against U.S. law. It is also a protected species under the CITES agreement.
Tortoise-shell chemistry & crystallographyChemicalNamekeratinChemicalFormulaSynthesisCrystalSystemNAChemistryClassificationOrganicNatureNaturalCrystallinityAmorphousChemistryComments
Tortoise-shell optical propertiesTransparencySemitransparent - SemitranslucentDispersionOpticalCommentsRefractiveIndex1.55-1.644
Tolerance:(-0.010)BirefringenceOpticCharacterNAOpticSignNAPolariscopeReactionSingly Refractive (SR)FluorescenceSWUV: Inert to moderate bluish white
LWUV: Inert to moderate bluish whiteCCFReactionPleochroismNone
Tortoise-shell characteristic physical propertiesHardness2.5CharacteristicCommentsStreakSpecificGravity1.26-1.35 Typical:1.29ToughnessFairInclusionsTortoise shell will have mottled coloration, numerous spherical particles that give it a dot like pattern under magnification. Plastic imitations will have a swirl like pattern.LusterWaxyStabilityFractureUneven, SplinteryCleavageNone