4.01-Carat Deep Blue-Green Montana Sapphire (Heated)


A deep blue-green heated Montana sapphire, very large for the locality at 4.01 carats.

In stock


This beautiful heated Montana sapphire is a rich deep blue-green color, strongly saturated but not so much that it blocks the beautiful flashes of blue as its held in the hand.  The gem shows a bicolored effect, with a darker band of blue in the center, while the two ends are a lighter blue-green.  The sapphire was heated in Montana to develop the color and improve the clarity; the treatment is permanent and stable. While the macro image shows a feather off to the side of the gem, its much more difficult to see in person. There is still a slight bit of rutile silk remaining, slightly softening the brilliance. I have factored the silk and inclusion into the price, making this a good value for the size–sapphires over 4 carats from Montana are exceedingly rare.

This sapphire is faceted in my custom “Testudo” oval brilliant design that I’ve designed and optimized for sapphire; the result is a glittering beauty of a gemstone.  The gem weighs 4.01 carats and measures 10.4 x 7.8 x 6.4 mm.  It would make an amazing center stone for a unique and one-of-a-kind engagement ring.

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