Up for sale is an early antique civil war sweetheart book with 4 photos, one being a civil war officer. The locket is small measuring 3/4" wide x 5/8" high. The latch is not tight, but I am sure could be adjusted. The design on the front cover with a cross a heart and an anchor makes me think this belonged to a Naval veteran.
This would make a great little doll accessory as well!
locket looks good but the photos got some scratchees