huge Victorian vintage brass ceiling medallion canopy for light fixture/chandelier

Huge antique, Victorian vintage, replacement repousse brass ceiling medallion or canopy for a hanging lamp or chandelier. It measures about 18" in diameter over the outer rim, 2 3/4" across the inner point and the center hole is about 7/8" across. This brass medallion is 3" thick and there are spots on the four ribs (show in the photos) where the brass is cut through, perhaps for hanging something like swaged strings of glass prisms, but we're not sure.

This brass medallion is in nice vintage condition with a patina of age and tarnish.