http://s159.beta.photobucket.com/user/Duanecrapser/media/Masonic-symbol-white.png.html?filters[term]=mason%20symbol&filters[primary]=images

Kinda looks like that but without the G in the middle. V + /\

I could be wrong, but I believe it's just random spawn. I just beat the game and I only saw 2 throughout the whole story. Also looking for more for trophy here.