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Synthetic Gem Materials and Simulants in the 1990s

Hanyang Univ.. Introduction. 90's technology : Development of manufacturing for synthetic gem materials and simulants ? with development of identification tech. Ex ) Diamond : MoissaniteRussia, China have high technology for synthetic gem using military technology Hydrothermal Crystal Growth

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Synthetic Gem Materials and Simulants in the 1990s

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    1. Synthetic Gem Materials and Simulants in the 1990s ?????? ? ? ? 2003. 10. 15

    2. Hanyang Univ. 90’s technology : Development of manufacturing for synthetic gem materials and simulants ? with development of identification tech. Ex ) Diamond : Moissanite Russia, China have high technology for synthetic gem using military technology Hydrothermal Crystal Growth – Ruby, Sapphires, Quartz, Emerald…

    3. Hanyang Univ. Synthetic Diamond : C, Diamond Cubic, 10 HTHP De Beers, 500hr: 14.2ct, yellow, ‘good’ JIK, 600hr : 34.8ct, yellow synthetic diamond Other Researcher : yellow, brown, brownish orange, brownish red… ? cause B, N GE & Russia : Near-colorless synthetic diamond. Prevent the boron and nitrogen

    4. Hanyang Univ. Synthetic Diamond : C, Diamond Cubic, 10 Short-wave ultraviolet radiation Metallic flux inclusion(yellow luminescence, phosphorescence)

    5. Hanyang Univ. Synthetic Moissanite : SiC, Hexagonal, 9.5 Physical, thermal properties are similar to diamond. Double refraction cause hexagonal st. ? Easy to separate from Diamond

    6. Hanyang Univ. Synthetic Ruby : Al2O3, Hexagonal, 9 Hydrothermal Crystal Growth Russia, Striated & Heavily roiled - Easy to separate from natural ruby using a 10× loupe

    7. Hanyang Univ. Anhydrous Crystal Growth Method Czochralski Pulling and Flame Fusion “Recrystallization” Industrial method of Al2O3 plate Flux-grown Synthetics Austria, 67ct Using tungstate fluxes containing Li and Mo Synthetic Ruby : Al2O3, Hexagonal, 9

    8. Hanyang Univ. Identification Synthetic ruby has glassy two- phase inclusion Triangular metallic inclusions, gas bubbles Synthetic Ruby : Al2O3, Hexagonal, 9

    9. Hanyang Univ. EDXRF (Energy Dispersive X-ray Fluorescence Spectrometry) Very useful in the separation of natural and synthetic rubies Synthetic Ruby : Al2O3, Hexagonal, 9

    10. Hanyang Univ. Synthetic Sapphire : Al2O3, Hexagonal, 9 Hydrothermal method Russia, variable colors cause amounts of transition metal Yellow : Fe, Blue : Fe+Ti, Green : Co, Orange : Mn, ……

    11. Hanyang Univ. Flux-grown method Grid-like structure of tiny inclusion in the synthetic sapphire Johnson et al, 343.33ct “Ti-sapphire” Identifying using UV Synthetic Sapphire : Al2O3, Hexagonal, 9

    12. Hanyang Univ. Identification Short wave UV radiation EDXRF analysis Synthetic Sapphire : Al2O3, Hexagonal, 9

    13. Hanyang Univ. Synthetic Emerald : Be3(Al,Cr)2Si6O18, Hexagonal, 7.5~8 Hydrothermal method China, Guilin Oriented needle-like tube, cone-shaped void Russia, Schmetzer and Kiefert Infrared spectroscopy in the 3500~3800cm-1 range

    14. Hanyang Univ. Synthetic Beryls : Be3(Al,Cr)2Si6O18, Hexagonal, 7.5~8 Hydrothermal method Russia Red beryl, aquamarine, bicolored beryls. EDXRF : Mn, Cr, Cu

    15. Hanyang Univ. Synthetic Quratz : SiO2, Hexagonal or Trigonal, 7 Hydrothermal method : Amethyst Russia, China, Brazil Widly used in the trade Difficult to detect Fourier-transform infrared spectroscopy Ametrine EDXRF Analysis : impurities such as Fe, Mn, Na, Zn

    16. Hanyang Univ. Synthetic Quratz : SiO2, Hexagonal or Trigonal, 7 Pink Quartz Russia, Flamingo quartz, grown in autoclave IR Spectrum : broad band around 3420cm-1

    17. Hanyang Univ. Synthetic Alexandrite : BeAl2O4, Orthorhombic, 8.5 Czochralski method : Allexite Flux-grown method Russia, Cr, V, Fe ? brownish red, bluish green

    18. Hanyang Univ. Synthetic Spinel : MgAl2O3, Cubic, 8 Flux-grown method Russia, Cr – red, Co - blue UV fluorescene, and absorption spectrum

    19. Hanyang Univ. Synthetic Forsterite : Mg2SiO4, Orthorhombic, 7 Czochralski method Japan, f 2.5cm, length 20cm Russia, pleochroism(blue and pink by Co) Lower refractive indeces 1.635~1.671 vs 1.695~1.702

    20. Hanyang Univ. Synthetic Opal : SiO2ˇnH2O, 5.5~6 Plastic-impregnated China, low density Sugar- and acid-treated Russia, low density Play-of-color Infrared spectroscopy

    21. Hanyang Univ. Miscellaneous Synthetics Sodalite : Na4Al3Si3O12Cl China Twinned colorless crystal Fresnoite : Ba2TiSi2O8, 3-4 Czochralski Tiny gas bubble

    22. Hanyang Univ. Miscellaneous Synthetics Yttrium Aluminum Perovskite(YAP) Czochralski pulling method Black, dark brown, dark yellow Phenakite : Be2SiO4, 7.5~8 Flux grow Russia, Brownish yellow

    23. Hanyang Univ. Miscellaneous Synthetics Zincite : Zn(Mn,Fe)O, 4 Poland, Vapor deposition Yellow, orange, orange red, yellowish green

    24. Hanyang Univ. Miscellaneous Simulants Amber : 2~2.5 Small chunks + brownish yellow plastic Madagascar Emerald : cabochon of colorless beryl Pearls : lead-based glass beads

    25. Hanyang Univ. Miscellaneous Simulants Tanzanite, Black Chalcedony, Black Diamond, Lapis Lazuli, Zirconia, Zambia ? kind of simulants

    26. Hanyang Univ. Conclusion Technology will continue to advance, and will bring improvements in existing synthesis techniques and the resulting products. The technology of gemstone identification also will move forward. Ex : UV, EDXRF, Loupe, FT-IR… Big 4 : Diamond, Ruby, Sapphire, Emerald

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