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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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1. Synthetic Gem Materials and Simulants in the 1990s ?????? 
? ? ?
2003. 10. 15 
2. Hanyang Univ. 90s 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, 343.33ctTi-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 : impuritiessuch 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: SiO2nH2O, 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 glassbeads 
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