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   ocr: during its geologic history. They give the sapphire its cloudy appearance but, more importantly, are oriented perpendicularly to the hexago- nal faces or sides of the original crystal. This alignment of needles yields the star effect as the needles in the three-fold pattern within the gem reflect incoming light in a star pattern. This effect is known as asterism, and, along with the beautiful color, is why star sapphires are SO highly prized. Such stones are polished in the domed shape you see here, called a cabochon, to best reveal the star, which moves 3 4