Red Opal

Red Opal is a trade name for opal with a deep red to reddish-orange body color, often overlapping with cherry opal and the redder grades of Mexican fire opal. It is valued for its warm, glowing intensity.

As hydrated silica it ranges from transparent to opaque, with the color produced by finely dispersed iron oxides. Most red opal is common opal, though some shows play-of-color.

Deep, evenly colored transparent red opal is among the more sought-after warm opals, while opaque red material is cut as ornamental cabochons.

Red Opal forms when silica-rich solutions, frequently linked to volcanic activity, fill cavities and fractures in rhyolite and similar host rocks. As the silica gel hardens into opal, iron oxides are incorporated, producing the red coloration.

In Mexican deposits, the opal grew in gas pockets and vugs within ancient lava flows where hot, silica-bearing groundwater circulated.

Mexico is the classic source of red fire opal; reddish opal also occurs in other volcanic opal fields and in some sedimentary opal deposits worldwide.

Identify Red Opal by its deep red to reddish-orange color, vitreous to waxy luster, and white streak, often glowing when backlit. Hardness is 5.5-6.5.

Most shows only body color, but some flashes green or rainbow play-of-color.

Look-alikes include carnelian and red chalcedony (harder at 7, no transparency glow), almandine garnet (harder, denser, crystalline), and red glass (bubbles). Opal's lower hardness, conchoidal fracture, and water content distinguish it.

Red Opal is faceted when transparent or cut as cabochons when more opaque, used in rings, pendants, and earrings. Deep, clean red stones command the highest prices among warm opals.

As soft, hydrous opal it requires careful handling, kept away from heat, chemicals, and dryness that can cause crazing.

Metaphysically, red opal is linked to passion, vitality, and courage. These associations are cultural; the stone's true value lies in its rich, warm color.