What does 966 mean when stamped on William rogers silver trays?

The number 966 stamped on William Rogers silver trays indicates the composition of the metal used in the piece. Specifically, it denotes that the item is made of a mixture of silver and other metals, typically containing 92.5% pure silver, with the remainder being other metals like copper. This marking is part of the broader practice of labeling silverware to indicate its quality and authenticity. William Rogers was known for producing silver-plated items, so the 966 stamp helps identify the specific grade of silver used in the tray.