Star Sapphires: Nature's Perfect Imperfection December 22 2015
Star sapphires are indeed a spectacular sight.
Ranging from a simple 4 point ray to a wildly complex and rare 12 point ray, these sapphires have astounded admirers for many generations.
Viewed best under a single source light such as the sun, a star sapphire, will parade its beauty through a natural phenomenon known as optical asterism.
As an untreated rough, a sapphire will often possess inclusions within its crystalline structure. These inclusions are often impurities such as titanium dioxide (rutile) which can appear in the form of needles or thin tubes.
Nature rolls the dice and sometimes, these inclusions line up in a parallel fashion perpendicular to the axis of the crystal. These tiny inclusions then concentrate their reflections into a single band of light giving the optical characteristic of a cat’s eye. By having inclusions lined perpendicular to multiple axes, the sapphire crystal can illuminate as many as 12 rays to form a beautiful star configuration. This effect, known as asterism, gives birth to the natural wonder of star sapphires which can be accentuated by shaping the sapphire in to a high domed cabochon with little to no heat treatment.
In the case for star sapphires, they are best worn as rings or bracelets as opposed to brooches, earrings or pendants. The orientation of rings and bracelets when viewed on our hands allow light to penetrate perpendicular to the base of the crystal which emphasizes the star effect. When choosing the perfect star sapphire, the elements of color, clarity, cut and carats still play a vital role in determining its value even though this unusual star effect is in itself an amazing phenomenon.
Star sapphires are a rare breed. They require an assortment of variables to align at the right moment to reveal its astounding beauty. So if you do get your hands on one, you’ll be sure to make a statement of natural beauty as a result of perfect imperfections.
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