Figures of the Article

• Dominican blue amber under different background illuminated by electric incandescent lamp
• Amber mining areas in Dominican Republic
• Amber-bearing surrounding rock in Dominican Republic
• Amber mines in Chiapas, Mexico
• The amber-bearing sandstone formation of the La Quinta formation
• Dark gray mazzantic shale with abundant amber
• Metallogenic regions of Myanmar amber
• Occurrence of surrounding rock in Myitkyina amber mining area
• Occurrence of surrounding rock in Hkamti amber mining area
• Gas chromatography-mass spectrometer (GC-MS) analysis for the chemical compostion of blue amber
• Fluorescence characteristics of blue amber samples from different origins
• Three-dimensional fluorescence spectrometer
• Fluorescent test accessory optical system
• Typical three-dimensional fluorescence patterns of blue amber samples from different origins
• Relative spectral power distribution of instrument light source (Xe lamp) and D65 light source
• Quantization limits of the fluorescent colour of blue ambers
• Quantization limits of fluorescent relative intensity of blue ambers
• Development process of the association standard Blue Amber Grading
• Different fluorescent characteristics of the same sample under different light sources
• Colour controller light box with D65 light source
• Conditions for observing the body colour of blue amber
• Conditions for observing the fluorescent colour of blue amber
• Classification of blue amber's fluorescent colours
• Grades of blue amber's fluorescent intensity
• The reference blue amber samples of fluorescence grades (only for show)
• The common body colours of blue amber
• Template credential of blue amber grading