Silver Mercury Glass Knob, Cabinet Knobs and Drawer Pulls, Tarnished Silver Mercury Glass, Vintage Antique Melon Style Dresser Knobs Antique silver metallic glass (also called mercury silver ) cabinet knobs for your kitchen and bathroom cabinets and drawers. Add a touch of elegance to your household cabinets, drawers or dressers with these antique cabinet knobs. Cabinet knobs are approximately 2.0" in diameter.