Found this button at an old homesite the other day. It has an iron back that is totally corroded. I suspect it’s a blazer button, but maybe something else? Can anyone ID this button?
Although, it should be noted they’re not actually from the Royal Blackheath, rather what the pattern gets called, as noted here: GolfTracer's - Royal Blackheath Clothing Buttons
So 20th century blazer button would be accurate.