More about the Thoriated Lenses

Count Rate Kodak Aero Ektar Lens 3,800 cpm.

The rear lens element is the radioactive one.  The radiation has caused the element to become slightly brown.

The serial number of the Aero Ektar lens is EE 16862.  This would date the lens to 1944.  It is labeled f:2.5  7In.

Michael Briggs has a page about Aero Ektars.

Graphlex.org has some interesting information about Ektar lenses including how to tell the manufacturing date from the serial no.

Count Rate Elgeet Militar Lens 800 cpm.

The Elgeet is labeled Elgeet Militar 3 inch (76mm) f:2.8  4289

Count Rate Xenotar Lens 2,400 cpm.

The Xenotar is labeled G.P. Goerz AM. OPT. Co.  Type I 6 IN F:2.8  No 800853  XENOTAR