Fine silver is marked .999 = 100% silver. Also called pure silver. Sterling silver is an alloy and is marked .925 = 92.5% silver and 7.5% other metals, usually copper. Argentium® sterling silver is a trademarked brand of sterling silver that resists firestain and tarnish. Not to be confused with “Argentium Argentine Plate” or “Argentum” which are nickel alloys containing no silver. Silver Filled is another material that is overlaid by a mechanical process with a layer of silver....