It is what's called a "snap-hook"... used for various purposes, not just as a clip on a swordbelt's scabbard hanger/harness. The photo below shows a similar one (but made or iron), on a US Cavalry Model-1859 Link-Strap. All of that being said, the ornate designs on yours indicate it was made for use on an expensive sword scabbard harness, or something similar.
Yours is missing the riveted-on iron "tongue," shown in the photo, and your brass main hook's tip is bent outward.
I have not seen one exactly like yours "solidly" documented as Confederate-made. It might be, but it also could have been manufactured sometime earlier than the civil war. There's an important difference in the meaning of the terms Confederate-made and Confederate-used. The wartime South was short on military equipment, and the abiility to manufacture it, so a lot of it was imported from Europe. Also, the Confederacy had no choice but to put a lot of "outdated/obsolete" early-1800s military equipment into service.