Gilson Imitation Lapis Gemstone & Information | Gemopedia by JTV | Gemopedia™
Gilson imitation lapis is a man-made lapis simulant that gives the look of the widely appreciated natural gemstone lapis lazuli. Because this imitation jewel has some ingredients and physical properties not shared with natural lapis, it is considered a simulant, as opposed to synthetic stone.
Intense Medium To Dark Blue To Violet Blue
Gilson-imitation-lapis classificationCommonNameGilson Imitation LapisSpeciesNAVarietyColorsIntense Medium To Dark Blue To Violet BlueAlternateNamesGemstoneGroupsKeySeparationsAppearance, RI, magnification and SG. Due to the porous nature the SG will change after the stone is soaked in waterClassificationCommentsMisnomer: synthetic lapis lazuli
Gilson-imitation-lapis chemistry & crystallographyChemicalNameChemicalFormulaSynthesisCrystalSystemNAChemistryClassificationNatureSimulantCrystallinityChemistryComments
Gilson-imitation-lapis optical propertiesTransparencyOpaqueDispersionStrength: noneOpticalCommentsRefractiveIndex1.53-1.55BirefringenceOpticCharacterNAOpticSignNAPolariscopeReactionFluorescenceSWUV: inert
Gilson-imitation-lapis characteristic physical propertiesHardness3CharacteristicCommentsStreakStrong BlueSpecificGravity2.33-2.53ToughnessFairInclusionsGilson imitation lapis will have vibrant and even coloration. Small amounts of minute pyrite particles will be evenly distributed throughout the stone. Surface of the stone might show many small angular, dark violet patches in reflected light. Pyrite inclusions will not have dark blue ring surrounding the inclusion.LusterVitreousStabilityFractureGranular, UnevenCleavageNone