Large Oval-Cut Purple Stone (likely Amethyst or Purple Glass) in Prong Setting

The item is a large, oval-cut synthetic amethyst or purple glass stone, likely part of a ring or brooch, given the visible prongs. The stone itself is a deep purple hue, with flashes of lighter lavender and fuchsia visible as light reflects off its facets. It exhibits a brilliant cut, designed to maximize sparkle and color saturation, featuring numerous triangular and kite-shaped facets on its crown and pavilion. The material appears highly transparent with no immediately visible inclusions, suggesting either a high-quality synthetic stone or very clean natural stone. The stone is held by at least four, possibly six, simple gold-toned prongs, which appear to be made of a yellow metal (possibly gold or gold-plated base metal) that is slightly discolored with age or wear. There are no clear maker's marks or stamps visible in the image. The overall style suggests it could be a costume jewelry piece or a more modest fine jewelry item likely from the mid to late 20th century, possibly 1950s-1980s, given its size and general aesthetic. The visible condition appears good, with no obvious chips or cracks on the stone. Some minor surface wear or scratches may be present consistent with handling and age, but these are not prominently discernible from the image.