Exciting! Alluring! Imagine the sense of awe the ancients must have felt when they first gazed at phenomenal gemstones. Imagine the thoughts that must have coursed through their minds! Now, open your mind to that same sense of wonder as you experience a gemstone that transcends the mystery of color, to the magic of phenomenal
Certain, special gemstones have the unique ability to display a majestic star pattern, the intriguing feline like cat's-eye, the almost hypnotic billowing sheen of moonstone, and the playful iridescent patterns of contrasting color seen in fire agates and ammolites.
The star effect, known as asterism, appears as rays of a star across the domed surface of the gemstone and is most often seen in ruby, sapphire, quartz, garnet and spinel. It is produced when a strong source of light reflects off of the multitude of geometrically arranged layers of threadlike inclusions that inhabit these unique gems.
If the threads in the gemstone all align themselves in a single direction, much like the strands in a spool of thread, the reflection will appear as a single ray of light called chatoyancy, or cat's-eye. The cat's-eyes occur in chrysoberyl, tourmaline and quartz.
The silvery glow that floats across the surface of a gem somewhat like a moonbeam across a fog enshrouded lake, is called adularescence, or the moonstone effect. Ammolite or fire agate have a rainbow effect similar to what occurs in brightly colored wings of exotic butterflies called iridescence.
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Information Courtesy of AGTA