Very bright colors in this natural Australian matrix opal from Andamooka area, which is nicely set into elegant 925 sterling silver pendant. Opal is about 8.5 carat (1.7 g), measuring 19x15x4.3 mm in size. Total pendant weight (opal + silver) is 3.34g. Setting and bail are 925 stamped silver, stamp is located inside the bail. 50cm (+5cm adjustable length) black twisted leather strap is included. Treatment: carbonized, no coating - stone is polished. Andamooka is famous for its matrix opals - when opal fills gaps in porous host material. Is getting more and more popular, as it can produce large stones with very good colors, and usually is less fragile than solid opal. Australian opal is sedimentary, formed slowly over millions of years. It's is not affected by contact with liquids, is stable and can last forever if takes care of.