Paraíba Opal are exceedingly rare blue gemstones, from Brazil’s famed Paraíba state. Displaying delicate bluish greens similar to a Caribbean Sea, Paraíba Opal is visually similar to the color of fine Paraíba Tourmalines, one of the world’s most valuable gemstones.
Hardness 5.5 - 6.5
Refractive Index 1.370 - 1.520
Relative Density 1.98 - 2.50
Named for its origin, Paraíba Opal displays delicate blues with a splash of green similar to a Caribbean Sea, and is visually similar to the color of fine Paraíba Tourmalines, one of the world’s most valuable gemstones. Translucency, color intensity and absence of unattractive imperfections are the key value determinants for Paraíba Opal.
Paraíba Opal is polished ‘en cabochon’ (cut in convex form and highly polished, but not faceted) in a variety of attractive shapes that beautifully captures its beautiful blues and translucency. Displaying an excellent luster, Paraíba Opal is carefully finished with a superior polish into attractive smooth domes with desirable proportions by experienced lapidaries.
One of October’s birthstones, Opal is from the Greek ‘opallios’, meaning ‘to see a change’. Opal without ‘play of color’ (flashes of color that change with the angle of observation), is translucent to opaque displaying a range of body colors including blue, green, pink, and yellow. The structure of Opals is comprised of tiny spheres of silicon dioxide forming a pyramid shaped grid, interspersed with water. Containing three to six percent water, it’s the refraction of light through these spheres that produces Opal’s characteristic play of color. Opal without play of color has its silicon dioxide spheres more randomly arranged.
Gem-quality Opals from Brazil first appeared in the London market in the early 70s. Aside from Brazil, other sources for Blue Opal are Peru’s Andes Mountains as well as British Columbia, Idaho and Oregon. Along with green and pink, attractive blues are a rare Opal color, commanding higher prices.
Only discovered in 2012, Paraíba Opal is from São José da Batalha in Brazil’s Paraíba state. Exceedingly rare, total production was less than 30 kilograms of raw crystals. Interestingly, the miners’ were looking for Paraíba Tourmaline deposits in the area, and until gemological tests relieved its true character, thought they had discovered a new Paraíba Tourmaline source. With no additional crystals unearthed since its initial discovery, Paraíba Opal is very limited and not available on the open market.
With over 90 percent of gemstones treated, Paraíba Opal is one of the few gemstones that are not enhanced.
Durability & Care
A relatively durable jewelry gemstone, Paraíba Opal (Mohs’ Hardness: 5.5 – 6) should always be stored carefully to avoid scuffs and scratches. Clean with gentle soap and lukewarm water, scrubbing behind the gem with a very soft toothbrush as necessary. After cleaning, pat dry with a soft towel or chamois cloth.