Greenish-yellow sapphire needs precise saturation to avoid tipping into a muddy olive tone — too little green and it's just yellow, too much and it dulls. This one holds the balance at full vivid strength, a bright chartreuse-gold with real electricity to it, eye clean, and cut with the kind of clean, even symmetry that lets every facet pull its weight — the stone is unusually lively, throwing light aggressively across a broad, well-proportioned oval face. GLC confirms natural sapphire with indications of heating, standard practice for this color category. Vivid, precise, and full of movement — this is greenish-yellow sapphire at its most confident.