Nice ID, Crusader.
Woodturner,
These all fall under the general heading of "flat buttons." If the one on the bottom is gun-metal-gray after you clean it with a toothbrush, then it is a tombac button. Several of my tombacs from Virginia had such a thick patina on them that I didn't even know what they were. Chip a little bit of the patina off with your fingernail on the edge of the button to find out. If it is still dark-colored, then they are both brass.
In terms of websites and books, there aren't many options for flat buttons. Most simply had "quality marks" on the back, rather than a manufacturer's name. By quality marks, I mean things like "extra fine" "extra rich" "gold gilt" "treble gilt" "standard color" etc.
Regards,
Buckleboy