The Tiffany & Co. 22555 M mark appears on sterling silver pieces produced by Tiffany & Co., one of the most prestigious American silversmiths. The number 22555 is a pattern or order number used internally by Tiffany to catalog specific designs or custom commissions. The letter M refers to the directorship of John C. Moore II, who oversaw Tiffany’s silver production from approximately 1907 to 1947. This mark confirms the piece’s authenticity, links it to a specific period in Tiffany’s history, and provides valuable information for dating, cataloging, and appraising the item.