Interesting group of finds.
I agree with tamrock. the small button looks enameled.
Never seen anything like it on here.
I dug an old enameled sparrow pin earlier this year and someone told me it was early 20th century.
I thought that one round ball item with the metal shaft protruding from it was a knapsack hook at first glance. It kind of reminds me of a bolt release on a rifle too, but it is probably too small for something like that.