18-30mm Blue Peruvian Opal Faceted Marquise have a translucent to opaque nature with a range of Caribbean to Seafoam Blues making this one of our favorite gemstones. Peruvian Opal is classified as Common Opal meaning that it does not have the `play of color` or rainbow-like flashes of color. Mined exclusively in the Ande Mountains, Peruvian Opal is highly prized for its wide assortment of blue and pink hues and its translucent quality which rival other stones for beauty.