1967 penny struck through 1 1

[Sandon]

      As we can only base our opinions upon the images that you post, please make sure that they show what you want us to see. 

     Based on the latest image that shows traces of the reverse, it is possible that this coin was struck through some soft material (generically referred to as "grease") on the reverse die or the planchet that mostly obscured the reverse design. See https://www.error-ref.com/?s=struck+through+"grease".  (It was not struck through cloth as on the examples you included in your Personal Message, as such pieces show the woven pattern of the cloth.) However, the reverse also shows discoloration and what appear to be scrapes, suggesting post-mint damage. While @J P M's explanation is also possible, this coin does not appear to resemble closely any of the examples shown on error-ref.com of one struck from a "capped die". See https://www.error-ref.com/?s=capped+die.

    If any of the reverse lettering is visible, does it read forward or backward?

   I still recommend showing this to Jon Sullivan and/or CONECA. Make sure to use images that show the remnants of the reverse design. In-person examination may also be necessary.