The mark is on a snuffer's tray sold in the UK earlier this year and is depicted in Ian Pickford's 2009 revised Jackson's Silver & Gold Marks, page 715.


The mark is also stamped twice but without a STER mark on a silver cup, which was in an American private collection until 2015.


I'm not aware of any other silver items with Whitney's maker's mark although it is possible others will turn up in the future.