Antique Victorian Cast Iron Floor ROUND Heat Vent Grille Grate 6" Louvers 1870

Just found at a local estate sale is this very nice beautiful old round floor grate! Just look at these photos!!  Has its working louvers with a cast iron grate top. Very decorative.   Fits a hole size 6" across and the overall size is 7 1/2" across the top. Engraved on the louvers "Butter & Bailley NY Patented June 10, 1870".  The cast iron is in very good condition; very decorative.  This is a very old Victorian cast iron floor grate!!