"Fire Opal" is a term used for colorful, transparent to translucent opal that does not exhibit a "play of colors" (this technically makes it a "common opal"). Instead of a play of color, fire opal has a bright, firey color that is present throughout the stone. Fire opal is usually orange to red in color, however, many people also apply the name "fire opal" to stones that are a bright yellow color.
Public Confustion with the Term "Fire Opal"
There is some public confusion between the terms "fire opal" and "play of color". Some people believe that a stone with a play of color should be called a "fire opal" and are surprised that the translucent orange and yellow stones are the true "fire opals".
How Fire Opals are Cut
Fire opal is cut in a variety of ways. Transparent fire opals are usually faceted and translucent stones are faceted or cut into cabochons. The orange fire opal shown at right is a faceted fire opal cut from material mined in Oregon. It is 9 millimeters by 7 millimeters and weighs 1.2 carats. The yellow stone on the right is a faceted fire opal cut from material mined in Nevada. It is a 9 millimeter round that weights 1.7 carats. The yellow stone below was cut as a cabochon from material mined in Mexico. It is a 19x17 millimeter oval that weighs 1.15 carats.