Opals of gemstone quality usually contain 6% to 10% water. … Precious opal is identified by the defining “play of color,” or the way in which colors change within a particular stone as it is rotated and tilted. The “fire opal” is a transparent or translucent opal ranging in color from yellow to orange to bright red.
Opals of gemstone quality usually contain 6% to 10% water. … Precious opal is identified by the defining “play of color,” or the way in which colors change within a particular stone as it is rotated and tilted. The “fire opal” is a transparent or translucent opal ranging in color from yellow to orange to bright red.