Royal Engineers engraved metal sweetheart brooch

British Army Royal Engineers gilt metal sweetheart brooch, featuring a design based on the regiment's traditional cap badge.
It has a central Royal Cypher 'GvR' surrounded by a circular belt representing the Order of the Garter. Inscribed on this is the motto of the regiment 'HONI SOIT QUI MAL Y PENSE' (Shame on him who thinks evil of it).
A laurel wreath frames the entire design, with a lower scroll reading 'ROYAL ENGINEERS'. The badge is surnmounted by a King's Crown.
The badge has an amateurish look to it, with the detail engraved into the gilt metal rather than impressed or cast. It is reminiscent of the smaller metal insignia added to the centre of regimental sweetheart brooches. However, this has had a horizontal pin clasp attached to the reverse. There is also a vertical loop or lug below the clasp and evidence of soldering/damage. No maker's marks are visible.