Hi Peter ,
I tried magnifying the picture odf the guy with 2 rifles and handling the brit prisoner and it just looks like a white spade emblem (per playing cards)with a fan below it. I thought maybe a dead dove or bread ,or a stash of wads, rifle cleaning rag .Naval or religious icon. need some input from Strelets .Couldnt find much from any other source, sorry i tried.probalyl a simple answer to it ...somewhere
I cant help you with sources, but looking at the figure reminds me that some pictures of Russians show them with medals on their chest. I seem to recall Russians were quite keen on wearing their medals in battle, and looking at it now I think that is the intention. Thats my guess anyway.