It is solid sterling silver that I’ve treated with liver of sulfur to create a darkened finish. The patina is embedded in the surface, but will polish with time and wear to show the bright silver underneath. Various factors (body chemistry, light exposure, etc) can slow or speed this change and it’s different for everyone. The best part about this finish is it’s low maintenance (no tarnish to worry about!). Cleaning is generally unnecessary but rinsing in warm water does the trick if needed. Most people love the timeless antique look darkened jewelry has with time and wear, but bringing it back to it's darker initial look is always an option.I offer re-darkening at no charge. Just ask!