Prior to the 1830’s, US Navy buttons were of a one-piece design, and were flat or slightly convex. They were beautiful buttons, most had the familiar eagle & anchor, some of the earlier ones had only an anchor. Some were American made, but there were many beautiful British made buttons too. (source: Record Of American Uniform And Historical Buttons, by Alphaeus H. Albert)
The ones pictured are from my collection (with Albert’s reference number under); with a close-up of one of my favorites (it was hard to pick just one…).
A very informative thread! There is discussion and pics on a few websites, sighting this particular button "with fowled anchor" were used on the dress uniforms of Marine Officers during the period.
Thanks for starting a great thread!