You could just look at this lot and say, oh hey, just a bunch of buckles. Not interesting, I don't make belts.
If you are an artist, however, you note that there are connecting possibilities on EACH CORNER of the buckle. So you could take goldtone jumps and connect them to make a collar necklace or maybe a bracelet, or make a pendant.
So what do you do about that bar in the center? Use as a base to wire on a small collage, such as maybe a burst of flower and leaf findings.
You could also bond on a 25x18mm bezel and set it with a small collage, a cameo or some inlay.
If you use as a pendant, you fill the center as above, then dangle drops from the bottom, and connect by the top (turn it around the other way, vertically.)
You could also use these as purse hardware
As you see now, there is much to be done with a buckle finding.