Recapping what I have seen...
The three small boxes contain "
plate number blocks," which were created by removing the plate number corners of some panes. All the blocks appear to be mint.
The black album contains mint hinged stamps, including some souvenir sheets. Also in the black album I have seen:
- stamped envelopes or wrappers (Scott# prefix "U" or "W")
- revenue duck hunting stamps (Scott# prefix "RW")
- air post stamps (Scott# prefix "C")
- defense postal savings stamps (Scott# prefix "PS")
- air post special delivery stamps (Scott# prefix "CE")
The covers depicted are a mixture of "first day of issue covers" (FDC's), perhaps historic covers, and one mint stamped envelope.
This collection is very well organized and in excellent condition. That speaks highly of the current owner (you) and the previous owner (your great-grandfather). Overall, it is more organized than my collection. Personally, I am transitioning my albums from
hinges to
mounts. Your photographs depict at least one stamp that I lack in my collection, though my speciality is used/canceled stamps (not mint).