The image above is from the gravestone of Cola S. Martin (1903 - 1984) and Wilma B. Martin (1907 - 1990) found in Magnolia Park Cemetery; Warner Robins, Houston County, Georgia. Notice the symbols on either side of the surname. The one on the left is a 3 chain link for the Independent Order of Odd Fellows. The one on the right is an R with a dove and crescent moon with seven stars for the Rebekah Lodge. I've tried to enlarge the images so they are easier to see below:
Stamped above the chain link symbol on Cola's side of the gravestone is another 3 chain links with F, L, and T inside. This stands for Friendship, Love, and Truth. It is an important principle of Odd Fellowship.
From their website (linked above), an Odd Fellow is "a person that is 16-18 years or older whom believes in a Supreme Being, Creator and Preserver of the Universe, and is faithful to their Country."
Rebekahs are described this way:
Odd Fellows, recognizing the need for a woman's touch and her helpfulness in carrying out the principles of Odd Fellowship, brought into being the Rebekah degree, founded upon the principles of faithfulness, hospitality, purity and dedication to the principles of the Order as portrayed by women characters of the Bible.Two more symbols I can now recognize and understand!
The degree was originally written for Brothers to confer on their wives and daughters and was considered an "Honorary Degree".
Later the Sisters were allowed to confer the degree on other Sisters, a ritual was adopted with the Sisters taking the parts. Rebekah Lodges were instituted and have continued to flourish.