Opal flashes colors as you turn the stone or move around it. This phenomenon is called play-of-color. An opal might show a single color, two or three colors, or all the colors of the rainbow! The best play-of-color is the brightest; if it also has all the rainbow colors, then it is very rare and valuable. Opals are known by their background colors and are called black, white, gray, or fire opals.
Opal shows a flashing display of different colors on a white, black, or gray background. Fire opals are usually orangy red.
The famous Roman scholar Pliny described opal colors as deep and rich as the colors used by painters.
Nessie is a two-meter (6.6-foot) pre-historic reptile called a pliosaur. Nessie’s bones turned into opal over millions of years.
Cody Opal, courtesy of The National Opal Collection
what's in a name?
The Romans gave opal its name – opalus, meaning “precious stone.”