platinum ring with rubelite and diamond

A platinum ring set with a large, bright red, step-cut rubelite (app. 12 carats), bordered with brilliant-cut diamonds and two baguette-cut diamonds in the prongs at each corner, with a tapered baguette diamond in the shank, signed: Bailey, Banks & Biddle. USA, circa 1950.
weight: 11 grams
ring size: 17+ mm / 6 ½ USA