The zinc KEESE Family Monument in the Rock Creek Cemetery at Washing D.C. displays symbols representing The Knights of Pythias—a knight’s helmet surmounts a shield with a skull and crossbones and three letters, “F”, “C”, and “B”, which stand for the fraternal organization’s motto, FRIENDSHIP, CHARITY, and BENEVOLENCE, overlaid on crossed swords.
The Knights of Pythias was founded by Justus H. Rathbone in 1864, making it the very first fraternal organization to receive a charter under an Act of the United States Congress. The society is based on the Greek story of friendship from 400 B. C. between Damon and Pythias, members of a school founded by Pythagoras.
According to their Website, Pythians: promote cooperation and friendship between people of good will, find happiness through service to mankind, believe that friendship is essential in life, view home life as a top priority, show an interest in public affairs, enhance their home communities, respect and honor the law of the land, and expand their influence with people of like interests and energy.
Gravely Speaking 
I am looking to purchase a Knights of Pythias metal marker to be placed at my great grandmother”s grave site, similar to a veteran flag holder.
Do you know of where I can purchase one?
I have been looking online to see if I could track down a source for the metal markers for the Knights of Pythias. I haven’t had any luck. What I would suggest, however, is that you go to your local gravestone seller and see if they can source it for you. Most likely they have suppliers for all sorts of markers for societies and organizations for members who are buried in the area.