Metal: 18k Yellow Gold Marked/Tested 18k Gemstones/Diamonds Diamonds - 4.03ctw Black Opal - 11.68ct Clarity: Vs1-Vs2 Color: F-G Measurements: 120mm X 70mm (Inch = 25mm) Weight: 34.3g Description: Laboratory Report # Us 58353101c June 28, 2011 Total Estimated Retail Replacement Value: $18,000.00 Weight: 11.68ct Shape And Cut: Mod. Cushion Brill. Color: Play Of Color Transparency: Opaque Refractive Index: 1.45 Spot L.W. Fluorescence: Weak Greenish Blue S.W. Fluorescence: Weak Greenish Blue Identifying Characteristics: Play Of Color, Structure Spectral Analysis: 480nm Conclusion: Natural Black Opal In Matrix Description: Yellow Gold Brooch Stamped "18k" Containing One Natural Black Opal Described Above. The Brooch Also Contains Side Diamonds That Are F-G Color, Vs1-Vs2 Clarity With A Total Weight Of 4.03ct. Total Weight Of The Brooch Is 34.3 Grams. Grades Weights And Measurements Are Approximate As Permitted By Mounting.