编号 99381764

编号 99381764

IGI Report Number: 746504147
• Species/Variety: Natural Topaz / Blue Topaz
• Shape & Cut: Cut Cornered Rectangular Mixed Cut
• Weight: 24.00 ct
• Measurements: 18.36 × 13.57 × 10.62 mm
• Color & Transparency: Blue, Transparent
• Characteristics: Natural inclusions
• Comments: Blue Topaz is commonly treated by irradiation followed by heat. Indicative evidence of treatment is typically lacking.
• Optical & Physical Properties:
• Refractive Index: 1.619 – 1.627
• Birefringence: 0.008
• Optic Character: Biaxial
• Specific Gravity: 3.53