The unusual brown swirl seen in these cabinet knobs reminds us of the Bennington brown door knobs of the mid 1800s to the early 1900s. To find these “mineral” knobs, however, in cabinet size is rare. In our 14 years of business, we have come across only a hand full. The mineral knob is made of clay, which is swirled and allowed to dry. Then a glaze is applied. These 1 1/2″ knobs are sold idividually. Each has an in-set screw back. One knob of the six is chipped. The other five are perfect. These highly sought after knobs are estimated to be at least 80 years old.