There are four localities where sapphires are found in Montana, and only one of them is a primary deposit–the others are all alluvial deposits. Montana is the only state in the United States with any significant production of gem-quality sapphires. There are rare star sapphires found in the Montana deposits, and the sapphires from Yogo Gulch are so famous that they are often referred to as “Yogo Sapphires.” There are no named varieties or species of Montana sapphire. The differing colors are the result of how the pieces were oriented before cutting, with the deepest blue being oriented on the c-axis of the original sapphire crystal. The large deep blue weighs 3.22 carats the three smaller stones are a custom radiant rectangle of 0.95 carats, a custom teardrop/pear of 0.45 carats and a trillion of 0.24 carats. This suite of fine sapphires were all faceted by me from a single large gem found on Jby Blaze Wharton at his mine on the El Dorado Bar on the Missouri River, outside Helena Montana. This has been helped by a growing appreciation for natural unheated gems and the wide variety of colors they come in before being altered by humans. However, the growing popularity of colored gemstones in general and American gemstones in particular have helped raise the profile of these gorgeous gems in recent years. While some of the Montana sapphires can be heated to produce more desirable shades of blue, many cannot due to the chemistry of the sapphires. Most of the sapphires from Montana are a pale green to blue-green when they are mined, with very limited numbers of deep blues and other fancy colors such as yellow, orange, violet and pink. Part of this is no doubt due to the fact that the most desirable blue sapphires are not common in the Montana deposits. However, even with all of that history they still do not have the recognition I feel they deserve. Sapphires have been known to occur in Montana for over 150 years and have been actively mined there for more than 100 years. All of the sapphires in this image are unheated and the sizes range from just under one carat to 19 carats. Sapphires found in this deposit exhibit a wide array of mostly pastel colors of low saturation, but they typically have high clarity.
In this image I’ve arranged a mix of rough and cut sapphire from the El Dorado Bar on the Missouri River in Montana.
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