Band ring with heart emerald cabochon and 2 diamonds

Band ring with heartshaped emerald cabochon and 2 brilliant-cut diamonds totalling ca. 0.10 ct, ca. WHITE (H)/SI, heart-cut emerald, 18K yellow gold, 4.5 g, ring size: 54, W: ca. 3.2 - 5.5 mm, late 20th century, minimal signs of wear, with hallmark 'GP'.