Common variety of colors, and they range from opaque to transparent. The most desirable opals are known as the precious opal. They have a special iridescent quality as you move, opal under light, and it shows a spectrum of colors.

Provide the best clues remaining of iridescent

1. Shimmering: The opals exhibit a mesmerizing shimmer or gleam as you observe them under different lighting conditions.

2. Rainbow-like: The opals display a beautiful array of colors, reminiscent of a rainbow, as you tilt or move them under light.
3. Multicolored: The opals showcase a variety of vibrant and contrasting colors, offering a captivating visual experience.
4. Ever-changing: The opals possess a dynamic quality where the colors seem to shift or change depending on the angle or intensity of the light.
5. Luminous: The opals emit a radiant glow or luminosity, creating a captivating visual effect that is often associated with opalescence.

Clue 1: Another term for the iridescent quality of opal is play of color.

Clue 2: The play of color in opals is caused by the diffraction and interference of light reflecting from the tiny silica spheres within the gemstone.

Clue 3: The colors exhibited by opals can include shades of red, orange, yellow, green, blue, indigo, and violet.

Clue 4: The intensity and variety of the colors in opal can vary depending on the angle from which it is viewed and the quality of the stone.

Clue 5: The play of color in opals is highly prized and often considered the most important factor in determining their value.

To determine the remaining clues of the term "iridescent," we can refer back to the information provided.

First, we know that opals have a special iridescent quality. This means that the opal exhibits a unique play of colors as it interacts with light.

Second, the opal shows a spectrum of colors when viewed under light. This indicates that the opal is capable of displaying a wide range of colors, possibly including shades of red, orange, yellow, green, blue, indigo, and violet.

Combining these clues, we can gather that "iridescent" refers to the quality of an object, specifically opals in this case, displaying a spectrum of colors under light due to its unique play of colors.