Precious Opal

 Precious Opal is the most valuable variety of the opal family. Its defining feature is the play of color, an iridescent display of shifting flashes in vibrant hues such as blue, green, red, orange, and violet, which move as the stone is tilted.

🔹 Key Characteristics:

• Composition: Hydrated silicon dioxide (SiO₂·nH₂O)

• Transparency: Usually translucent to transparent

• Body Color: Can range from white, gray, brown, black, or even colorless, always showing play of color

• Hardness: 5.5 – 6.5 on the Mohs scale (relatively delicate)

• Sources: Major deposits are found in Australia (the world’s leading supplier), Ethiopia, Mexico, and also Brazil (notably in Piauí and Bahia).

🔹 Difference from Common Opal:

• Common opal does not display play of color, appearing only milky, translucent, or solid-colored.

• Precious opal is considered a true gemstone precisely because of its optical phenomenon.

🔹 Value:

• The more intense and diverse the colors, the higher the value.

• Black opal with vivid fire is the rarest and most expensive.

• Prices can rival or even exceed those of high-quality sapphires and emeralds.