Copal Gemstone & Information | Gemopedia by JTV | Gemopedia™
Copal can be thought of as 'baby amber.' Like its much older counterpart, it is a hardened resin that originated as tree sap. Copal is similar in both appearance and chemistry to amber. Opinions vary from source to source as to when copal becomes amber, but the general consensus is that organic resin younger than 10 million years old is copal, while anything older is amber. As amber can be as old as 360 million years old, copal is substantially younger.
Yellow, Orange, Brown
Copal classificationCommonNameCopalSpeciesNAVarietyColorsYellow, Orange, BrownAlternateNamesGemstoneGroupsKeySeparationsFluorescence, SG, salt water float test. Acetone will attack copal rapidly but not amberClassificationCommentsCopal is an immature (young) version of amber.
Copal chemistry & crystallographyChemicalNameChemicalFormulaamorphous organic material fossilized resinSynthesisCrystalSystemNAChemistryClassificationOrganicNatureNaturalCrystallinityNon-CrystallineChemistryComments
Copal optical propertiesTransparencyTransparent - TranslucentDispersionOpticalCommentsRefractiveIndex1.54-1.54
Tolerance:(-0.010)BirefringenceOpticCharacterOpticSignPolariscopeReactionSingly Refractive (SR) With ADRFluorescenceSWUV: Inert to strong bluish white more than amber
LWUV: Inert to weak bluish whiteCCFReactionPleochroismNone
Copal characteristic physical propertiesHardness2CharacteristicCommentsStreakSpecificGravity1.1-1.03 Typical:1.06ToughnessPoorInclusionsCopal might show surface crazing.LusterVitreousStabilityPoorFractureConchoidal, UnevenCleavageNone