The back fin does seem to have a chipped tip that is rough.

The VTG MIKASA Leaping Dolphin Crystal Decanter Bottle Topper is a unique and elegant addition to any kitchen or barware collection. Made of crystal with a clear color, this dolphin-shaped bottle stopper adds a touch of sophistication to wine or liquor bottles. The detailed design of the leaping dolphin make it perfect for those who appreciate animal-themed decor and quality craftsmanship. This set includes one beautiful decanter topper from the reputable brand Mikasa.