WW1 Simple Mizpah Brooch

This is a really special little Mizpah brooch, that has caused much debate and discussion between us!
Made from brass, and in the form of a safety pin we are confident in dating this as a WW1 Sweetheart piece.  However, we are unsure if it was meant to be part of a larger item, or could potentially be an item of Trench Art.

This brooch measures 4.3cm in width by 0.5cm high.