It's very possible that this is oil but in my 15 years of doing this, I'm still not confident enough to say for sure.
What I can tell you is that this is beautiful. Beautifully moody with the most lovely combination of colours. Solid wood carved frame.
Frame measures 23-1/2" in height x 27-1/2" in length x 1-1/4" in width.
Canvas measures 19-1/2" in length x 15-1/2" in height.
Age appropriate wear but really, this is in beautiful condition.