Joe, Hamelmans book is excellent. Covers ALL aspects of the badge from 1914 to 1957, even the infamous 'Chaplains' badge and the 20 July 1944 pieces. Really, everything, boxes, docs, pins, KM type and specs on all. Quick and right to the point, an easy read and more important written easy to remember!

Seems like these WW1 badges anything went. Cut outs, screw backs, silver / gold plating. If you had the money you could get whatever you wanted..

WW1 badges the variations are in - helmet shape/rivets,,pebbling,,swords and bows..

Joe,If the pebbling on yours is on the flat side it looks to be the type 3 badge. ,G.