One of the most interesting glass knobs has to be the purple. Specifically, the purple that comes from manganese oxidizing when exposed to UV rays from the sun. Over decades a beautiful purple develops. This process happens in different rooms and degrees of sun light, so the purple intensity will vary. Truly a gorgeous set of special door knobs. Sold as a pair of 2.
Condition: Good used condition, design is bright, one knob is slightly more purple-y than the other one, one has a few scratches on the top (shown in last pic), collars have wear, replaced one of the set screws.
Diameter of knob: 2 1/8"
Projection: 2 1/4"