I dug this button today, it was my last hole of the day and my only good find, I thought it was a WW1 button, happy to not get skunked! I just started to examine it and its not like any WW1 great seal button ive dug ( I have several) this one has {I.S.} above the eagle and {MICH.}Under the eagle. The back mark needs to be detailed but i usually wount clean or preserve until I know exactly what I am dealing with, Figured some history genius on here may be able to help? Quick internet search yielded nothing.