Found at the farm in the “blue” room’s closet. No name but has:

• Inset heat ring with single notch opposite handle at 12 o’clock.
• ¾” high size number at 12 o’clock
• Raised small molder’s mark letter at 6 o’clock

Those bullet descriptors were taken from The Cast Iron Collector’s web page on 6/7/13 where he says they indicate the skillet is  a Lodge made in the 1930’s to 1940’s.

The photo below was taken when at the farm but shows a three-notch; 12 SK, Made in USA with molders mark as D. ????????????