lovely historic blade Atlantia with a clearly tempered edge & some lamination near the edge as well, I expect the patterns could be brought out further to show whether its an inserted laminated edge with softer backning envelope or not. That would be my guess based on the current photos.
This thread shows a later possible related British Indian army style.{or not as the case may be.} that may or may not be of intrest.
linky....
Spiral.