Post WW1 quantities of unfinished Mills grenade castings were sold off at auction and many were made into ink wells and moneyboxes. This is most cases wasn't trench art as it was done industrially. Indeed a design was registered in 1915 for a Mills Moneybox.
Here are some photos of two I have. The No 5 features a filled in filler hole. Please also note the M cast into the upper body. The coin slot is between the upper segments. In the case of the No 36 (or possibly 23 Mk III) the slot has been cut across the top of the front of the grenade.



The No 5 has a purpose made tin base. The No 36 has a small pin drilled and inserted into the base thread to stop a baseplug being screwed so far it will drop into the body. Signs of someone thinking about what children do!
I hope this is of interest.
John
Here are some photos of two I have. The No 5 features a filled in filler hole. Please also note the M cast into the upper body. The coin slot is between the upper segments. In the case of the No 36 (or possibly 23 Mk III) the slot has been cut across the top of the front of the grenade.



The No 5 has a purpose made tin base. The No 36 has a small pin drilled and inserted into the base thread to stop a baseplug being screwed so far it will drop into the body. Signs of someone thinking about what children do!
I hope this is of interest.
John