I had about 30 minutes this evening to check a freshly cleaned out ditch and hedge row beside a late 1800s homesite. The button is ART METAL WORKS. The penny is just there for size. Needless to say, I'll be back.
That is a US Great Seal button. I can't give an exact date but I believe it is from WW1-WW2. They have been used from WW1-present on military coats for US soldiers. Great finds.