Two brooches (King Edward and Royal Artillery)

[Noor]

Hi guys,

After busy day of spending money, I will sell two of my brooches. Before I stick them up for a sale, I would like to ask advise of the price and also maker marks on them.

1. VERY nice gold and diamond Royal Artillery sweetheart brooch. There is stamping on the back and some number. No idea what the number means but the stamp I presume shows gold contest. Any help with the value?