Speaking as a 30-something-years artillery projectile and fuze collector (and book-author on those subjects), I can tell you with certainty that the large brass threaded object is definitely not an artillery fuze. Various people have guessed that it is some type of valve-body or barrel plug, but no proof of its ID has yet surfaced.
The small triangular-shaped object is the keyhole-cover from a civil war era carpetbag lock... if I'm remembering correctly.
The small 1-piece stamped-brass button shows the "three feather-plumes" emblem of the (British) Prince Of Wales. Having a "rope border" around the edge indicates it MAY be a military button... but I am not familiar enough with every variety of British military buttons for certainty about that. The backmark of your 1-piece brass button saying "Extra Rich Quality" in INDENTED (not raised) letters dates it from about 1810 into the early-1840s.
