The locket holds a photo and a round sample of hair. 

In the circular center of the half containing the hair, it is marked  "W&H 1/4 GOLD SHELL."

 Made in the United States during the Victorian era. 

The pendant was made by  "Wightman & Hough" and is adorned with intricate engraved initials.  SEE PHOTO 

Diameter is slightly over 1 1/8th inch