Peruvian Opal — Andean Common Opal in Pink and Blue
Peruvian Opal — Andean Common Opal in Pink and Blue
Non-iridescent body-colour opal from the Andes, cut for accessible coloured-stone jewellery
Peruvian opal is common opal from Peru, typically in pink or blue body colour, without play-of-colour. Also marketed as Andean opal, the material is found in volcanic and sedimentary deposits in the Andes mountain range, principally in the southern departments of the country, and is cut en cabochon for use in earrings, pendants, beaded work, and entry-level fine jewellery. The species lacks the value and prestige of precious opal from Australia or Mexico but offers a consistent supply of attractive coloured material at accessible price points.
Composition and colour
Like all opal, Peruvian opal is a hydrous silica, SiO2·nH2O, with water content typically in the 3 to 10 percent range. The pink colouration is attributed to traces of palygorskite or other clay-mineral inclusions, with refinements still under investigation in the mineralogical literature. The blue colouration of the blue Andean material is similarly attributed to trace mineral inclusions and to specific scattering effects within the opal structure. Neither colour shows the diffraction-based play-of-colour characteristic of precious opal — the body colour is the entire visual character of the material.
Pink Peruvian opal ranges from a pale, almost translucent rose to a saturated salmon-pink, with the most desirable material showing even body colour and good translucency. Blue Andean opal varies from pale sky blue to a deeper, almost turquoise-like hue. Both colours can show dendritic inclusions of manganese oxide, producing attractive natural patterns within the body that some buyers value as natural artistry rather than as inclusions to be avoided.
The species is translucent to opaque, with a hardness of 5.5 to 6.5 — slightly softer than the standard 6 to 7 of fine quartz — and a refractive index in the 1.43 to 1.46 range. Specific gravity is around 1.98 to 2.10. The lower hardness compared with quartz means Peruvian opal requires care in setting and wear, and the typical opal cautions about thermal shock and dehydration apply, though to a lesser degree than for precious opal because the body is less dependent on water structure for its appearance.
Sources
The Lily Mine, also called the Pisco Mine, is the principal commercial source of pink and blue Peruvian opal, located in southern Peru in the Acarí district of Caravelí Province. The mine has produced consistently for several decades and supplies the bulk of material reaching international markets. Other smaller deposits in the broader Andean region produce additional material, with collective output sufficient to support steady international supply at modest prices.
Production from the Lily Mine has shown some quality variation over time, with periods of higher and lower yield of fine-grade material. Buyers paying premium prices for top Peruvian opal should be aware that the highest grades are an intermittent product rather than a guaranteed mine output.
Cutting and use
Peruvian opal is cut almost exclusively en cabochon, oriented to display the body colour and any decorative dendritic inclusions to best effect. Faceted material is occasionally encountered but rarely impresses, as the body lacks the brilliance of a higher-RI gem. Bead and tumbled-stone production is the major output of lower grades, with cabochon production reserved for the better material.
The species takes a high polish and presents well in silver and gold settings. Bezel settings are preferred for protection of the relatively soft material; prong settings are workable for occasional-wear pieces but not ideal for daily-wear rings.
Quality and price
Quality grading favours even, saturated body colour, absence of fractures and surface flaws, good translucency, and decorative dendritic patterns where present. Pink material is generally more sought after than blue, with the highest grades commanding several times the per-carat price of commercial-grade material. Even at the top of the range, however, Peruvian opal trades at a small fraction of the per-carat price of fine Australian or Mexican precious opal.
The accessible pricing has supported broad use of Peruvian opal in contemporary fashion jewellery, beaded work, and entry-level fine jewellery. Major retailers and independent designers alike have built collections around the material, often pairing it with sterling silver or 14-carat gold settings to maintain accessible price points.
Care
Peruvian opal benefits from the standard opal care guidance: avoid prolonged exposure to extreme dryness, sudden temperature changes, ultrasonic and steam cleaning, and harsh chemicals. Cleansing should be by mild soap and warm water, with a soft cloth for drying. The lower water content of common opal makes it less prone to crazing than precious opal, but caution remains warranted.
In the trade
Skyjems treats Peruvian opal as a useful entry-level coloured stone for contemporary design, with reliable supply and consistent visual character. We recommend bezel-set or otherwise protected settings for daily-wear pieces and standard opal-care guidance for cleaning. The material does not require laboratory documentation in most price ranges, although laboratories can confirm identity and natural status if requested.