Ypres paper knife

This paper knife is made from a German cartridge case with a German crest soldered onto it with a bronze blade (probably made from a shell case) decorated and with the word Ypres. It was probably made my a German soldier and acquired by my father at some time during his service with the Coldstream Guards on the Western Front. His unit spend several months at Ypres during 1916 and 1917. The war museum classifies this kind of thing as "trench art".

My father's full name was John Hubert Fox, service number 14269. He enlisted on 21 Dec. 1914 at Sheffield, serving on the Western Front in the 2nd Battalion, Coldstream Guards. He was wounded on the Somme in Sept. 1916 and more seriously at Cambrai in November 1917. After recovery in
hospital in Manchester he was posted to the Reserve Battalion at Windsor where he was engaged in training recruits. He was demobbed on 10th March 1919.
There are extracts from his letters home published in the Derbyshire Times of 29th Jan1916, 11th March 1916 and a third one which I haven't been able to date.

Editor's Comment:
Trench art paper knife in the form of a scimitar, copper blade with punched decoration and 'Ypres'; handle made from a French 'Lebel' round, with German button (Crown surrounded by motto 'Gott Mit Uns') added.