: Thin slices of opal glued to a dark backing (and sometimes capped with quartz). These offer the look of expensive black opal at a fraction of the cost—often around 1/30th the price of a solid black opal. Check Play-of-Color & Pattern :
: Ensure the jeweler provides a Certificate of Authenticity stating the opal’s origin and any treatments (like smoking or sugar-acid treatments). buy opal earrings online
: The rarest and most valuable; it has a dark body tone (N1–N4) that makes colors appear more intense. : Thin slices of opal glued to a