Yeah you're right, modemac has a lot of great info but some of the details from one page to another can sometimes seem a little contradictory. I assume it's from him learning more information but not always updating every relevant detail site-wide. Here's my understanding:
The change from Red Mountain to Century happened in 1957. But it was only a branding change, only affected the labels; the holloware was produced using the exact same patterns and manufacturing methods, and in most cases examples of Red Mountain and early Century are indistinguishable.
It wasn't until the introduction of DISAMATIC automated production that things changed; the earlier patterns were not compatible so they had to make new ones. This conversion to automation started producing items in 1966. And Century series produced via automation are distinguishable from the earlier manual ones.
As a result, early Century produced prior to automation are often called Red Mountain these days, since there's no practical difference. Modemac's pages are an example of that, as his main BSR page clearly delineates the Red Mountain to Century switch as 1957, yet his saucepan page lists Red Mountain as to 1966, where he dates the markings.
But any 2 QT saucepans made prior to 1966 would show Red Mountain markings regardless of which brand they were sold under, and those markings on the pot were 2QT on the top of the handle near where it met the pot. Since yours had the markings on the bottom, that indicates it was one made after the conversion to automation, so at least 1966.
And then the lids for this saucepan, apparently there is a distinguisher between Red Mountain and early pre-automation Century, and that is RM had basting dimples on the underside of the lid while Century were smooth. Personally I'm unsure if the timing of dropping the dimples and changing of brand names were exactly synced. But post-automation, they switched from loop to tabbed lid handles for the reason I mentioned earlier.
But the "Made in USA" question, I overlooked that - apparently there was nearly a two-year gap between the switch to automation and the inclusion of the "Made in USA" markings, which started in late 1967 through 1968. Thus there are examples of post-automation Century that are not marked "Made in USA", and that narrows the manufacture date of your saucepan down to between 1966 and 1968.
I want to qualify all this as that I'm entirely dependent on the accuracy of modemac's info; I certainly wasn't involved 1st person.
And apologies for going into this detail on your recipe thread, though the saucepan in question was used to make the recipe. Hopefully the topic was relevant enough to warrant inclusion here.
