Blue Green Sapphire – Round .81Ct. This Montana sapphire is a beautiful and nearly flawless gemstone. It is a medium blue color in daylight with a slight bluegreen in artificial light. Just a very small fingerprint inside this All American Sapphire™ that is not visible with the naked eye and does not affect it’s brilliance. This .81 classic color change rock Creek sapphire is virtually flawless and so displays a distinctive diamond like brilliance. It is an excellent diamond simulant with medium blue color in daylight and a distinct color shift to teal in fluorescent light.