Twin Galaxy Stones
A stunning pair of nearly identical Lightning Ridge Black Opals. These rare stones are both more valuable and far more fragile than diamonds. Opals are a hydrated amorphous form of silica. The internal structure of precious opal makes it diffract light and can take on many colors. Precious opal ranges from clear to almost any combination of colors. Of these hues, the reds against black are the most rare, whereas white and greens are the most common. They vary from opaque to transparent. Because of its amorphous character it is classed as a mineraloid, unlike the other crystalline forms of silica which are classed as minerals.
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