Hard to say... they haven't changed much in 200 years. From what I can see it is not spun, so older sterling/coin or not so old silver plate.
If it is sterling it is pre-1850's technology. Probably pre-1900.
If it is coin it is pre-1850-ish. This would be my guess, but you can't be sure without testing it.
The spun sterling stuff is always thin and has a rolled edged. Yours doesn't have a rolled edge.