I found this New York button in Virginia a while ago. Looks post Civil War to me, but I’m not sure when it was made. Any idea? No back mark by the way.
There is a set of 4 on ebay...no real description except "vintage".
There is one on Kelly Badges without the horizontal lines...it says police and prisoner uniform button... Again no time period given.
Your New York State Seal button is shown as NY-31B in the Albert button-book... which says it is definitely from after the civil war. Specimens of it which have a backmark say "WATERBURY BUTTON CO / CONN." The book also says these "Later" (meaning, post civil war) NY Seal buttons are known to have been worn by city/town employees, not just NY State Militia troops.