One of the most sought-after colored gemstones in the world, the color-changing sapphire possesses the rare ability to change color depending on the light. Weighing 12.40 carats, this example of the coveted gem is certified as an untreated color-changing sapphire of Ceylon origin by the American Gemological Laboratories. The captivating, cushion-shaped mixed-cut stone displays a beautiful classic blue color when viewed in daylight and an equally stunning violet hue when viewed in incandescent light. It is set alongside two white diamonds totaling 1.47 carats in its platinum setting.