Finally rain and a good hunt!

After 6 weeks of no rain at all we finally had an all day soaker yesterday so took an hour and hit the neighbors freshly cut alfalfa field. Only got an hour in when it started raining again and I gave up for the day but I pulled a few rusty square mails, farm implement parts and these 4 flat buttons. 2 were marked. First was marked HT&D which apparently was made 1800-1812 and the second was Will Cleaver London marked.... pre Civil War?

If anyone has any knowledge on these please let me know. Thank!

Steve