Wonderful ! If you noticed , there are writings per lens , one with ink pen and newer one with the carbon pencil. I saw BAF at one of the later written pencil notes. BAF reminds me Barium Fluoride . Do you know when BAF invented , I invested to google but could not find.
If later lenses is fluoride based , they say they are very sensitive to atmosphere. I have 111mm f:1.5 Fluro Ektar and 10 pounds weight and what an amazing lens. I advise you to hold your lenses with hand and look to someone at night. If you see the detail , noise , plasticity , shadow , skin detail increase , curves are more visible , you would notice that your lens sees more than the eye.