does anybody know what this mark is? SD on earrings.

[cocoscloset]

Hello, the earrings have stylized SD on back.   I am very inexperienced with jewelry so I really appreciate any help.  thank you, c. king

[mooncat_watches]

If the SD is stylized you should probably include a pic?

[cocoscloset]

thank you!  I did try to include this picture but it did not show up. 

[cocoscloset]

and I take horrible pictures