The one shown on the IWM website is disappointingly well polished but that is not too surprising if it was held as a decoration or display piece in an officers mess etc.
IWM list it as Gunmetal (known as Red Brass in the US) but looking at the colour of it I doubt that.
Gunmetal is an alloy of Copper, tin and zinc in that order of proportion and tends to be a greyish colour.
Brass is an alloy of Copper and Zinc whilst Bronze is an alloy of Copper and Tin. Neither of these could be described as "Greyish".
Whilst looking into this I find that the most likely action to result in the capture of these items was Megiddo, Palestine in 1918;
Battle of Megiddo | National Army Museum
I believe there were some 300+ guns captured so I wonder how many had these crests and of those how many have survived.
It will be of interest to our Antipodean members the Allenby's force included a large number of ANZAC troops so perhaps I can interest you blokes in my quest for more info?
Here's an Australian Government link;
Meggido: Allenby's Masterstroke
Regards
Mark
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