Hello Tom,
This key looks genuine to me. This type of key was made by Chubb for their smaller locks, as found on cash and deed boxes. Locks for book-edges, small trunks and travelling bags also used these small keys.
The majority of them have a turning point on the top of the bow; many other makers used a turning point inside the bow, even in very small keys. The smallest of the eight keys in the photo is just 1″ long.
Karl.
