3.11-Carat Deep Midnight Blue Montana Sapphire (Heated)


A beautiful deep midnight blue heated Montana sapphire in my custom Helena brilliant oval design, quite large for Montana at 3.11 carats.

In stock


This beautiful heated Montana sapphire is deep midnight or indigo blue–one of the deepest hues I find in the Montana gems.  The color was developed by heating the gem in Montana, but no other treatments were made to the gem.  The treatment is permanent and stable and not only develops the color, but also improves the clarity.  There are some minor feather inclusions in this gem, but they tend to be lost in the deep color.  It can appear very dark, just showing flashes of blue on a dark background.  Due to the inclusions and dark tone, I have priced this very competitively, making it a great value for the size.

This sapphire is faceted in my custom “Helena” oval brilliant design that I’ve designed and optimized for sapphire; the result is a glittering beauty of a gemstone.  The gem weighs 3.11 carats and measures 9.3 x 7.7 x 5.7 mm.  This is very large for a Montana sapphire; each year I manage to get only a handful of sapphires large enough to create a finished gem this size.  It would make an amazing center stone for a unique and one-of-a-kind engagement ring.

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