3.87-Carat Deep Peacock Blue Montana Sapphire (Heated)


A beautiful peacock blue heated Montana sapphire in a custom square cushion design, 3.87 carats.

In stock


This beautiful Montana sapphire is a gorgeous deep blue-green color that I call peacock blue, as its reminiscent of the color of the peacock’s feathers.  Unlike most of the Montana sapphires I offer, this one has been heated.  The heating was done here in the United States, in Montana, and was the only treatment done.  It is permanent and stable.  The heating dissolved the gray rutile silk in the original rough, allowing the blue color to develop, and making the gem clear and transparent.  There is one small feather off to the edge of the gem but it is not easily visible with the naked eye due to its location and orientation.

I faceted this sapphire in a new brilliant square cushion design that I created and optimized for Montana sapphire; the result is a glittering beauty of a gemstone. The gem is quite large for a Montana sapphire: It weighs 3.87 carats and measures 8.5 x 6.1 mm; the perfect size for an engagement ring.

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Product Enquiry

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We're often asked about this, and yes, we do include our own certificate of origin and authenticity.  You can learn more here: https://www.earthstreasury.com/what-about-a-certificate/

Can I have a custom piece of jewelry made?

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What is your return policy?

We have a one-week review and return policy that starts the date you receive your gem.  We want you to be 100% sure you have the right gem.  Learn more here: https://www.earthstreasury.com/risk-free-review-and-return-policy/