English: Opal; A Universe in a Stone
Introduction:
Opal is arguably one of the most mesmerizing and unique gemstones in the world. Unlike other gems with a single body color, opal's beauty lies in its "play-of-color"—a dynamic rainbow-like display that shifts and changes with the angle of observation.
Cause of Play-of-Color:
This remarkable phenomenon is due to opal's internal structure. It is composed of microscopic silica spheres arranged in a regular, three-dimensional grid. This structure diffracts white light, splitting it into the stunning spectral colors, much like a prism.
Types of Opal:
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White Opal: Has a light or milky background.
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Black Opal: Features a dark body tone, which provides a greater contrast for the play-of-color, making it the most valuable type.
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Crystal Opal: Is transparent or semi-transparent, with the play-of-color visible within the stone.
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Fire Opal: Known for its vibrant orange and red body color, typically without play-of-color.
Conclusion:
Opal is a gem that seems to capture fire, lightning, and a rainbow within itself. Although it requires special care due to its relative fragility and water content, its unparalleled beauty has made it legendary among collectors.