Blue Opal

Blue Opal is a variety of common opal with a soft blue to blue-green color. The most celebrated source is Peru, where Andean blue opal is mined in the mountains alongside pink opal.

Unlike precious opal, blue opal usually lacks play-of-color; its appeal lies in a tranquil, sea-like blue that can range from pale sky blue to deeper teal, sometimes with white, brown, or dendritic markings.

Its gentle color and translucency make it a popular gem for cabochons, beads, and pendants, often marketed as a soothing, ocean-inspired stone.

Blue opal forms from silica-rich solutions deposited at low temperatures in volcanic rocks, fractures, and weathered zones. As the silica gel hardens into hydrated opal, trace copper and other elements can impart blue and green tints.

In Peruvian blue opal the color is often attributed to trace copper minerals and fine inclusions. The opal fills seams and cavities in the host volcanic rock.

Major deposits occur in the Andes of Peru; other blue and blue-green opals come from Oregon (Owyhee), Indonesia, and elsewhere, though Peruvian material is the best known.

Identify blue opal by a soft, even blue-to-teal body, translucent to opaque, with a waxy-to-vitreous surface and typically no play-of-color. Some stones include white cloudiness or black dendritic patterns.

Opal is amorphous, hardness 5.5-6.5, with conchoidal fracture. It is softer and often more translucent than dyed look-alikes.

Distinguish genuine blue opal from dyed howlite or magnesite (grey veining, color that can rub off), from blue chalcedony (harder at ~7, more uniform), and from imitation glass (overly even, bubble-bearing). Natural blue opal usually shows subtle internal variation in tone.

Blue Opal is used primarily in jewelry as cabochons, beads, and pendants, valued for its calming, ocean-like color. Peruvian blue opal in particular is popular in artisan and beach-themed designs.

It is also carved into small ornamental pieces and tumbled for collectors. Cleaner, more vividly colored stones command higher prices.

Metaphysically blue opal is associated with calm, communication, and emotional soothing. These are traditional and spiritual beliefs, not scientifically supported facts.