China!
It is old, I pin this as just post turn 1900, perhaps 1910-30, although most of the cutoff I believe for this type was around 1910 despite the hint to an art Deco style.
I can't remember if they call this exact variety the "antique finish" Chinese rugs or not, this may only be for the Peking antiques.... Anyway, without going into too much detail, this is what is more conveniently, and generally known as an "
open back" chinese. This "open back" terminology is really only used for Chinese Rugs, although other carpets from various areas in NW Persia may have similar orientation including some
Peshawar Caucasian Kazak carpets. I say conveniently because when you see detail of the back, you can see both sides of the knot. In this example, you see one large node of the knot, and an additional smaller node adjacent. Both the same knot, but it's "open" to see both sides.
As for the value, it's in rough shape. $1800 is a really high assignment to value if Its around a 2x3 which it appears. What size is it?
Personally from a decorative standpoint I think it's kinda neat to have an old rug show signs of use, but from a collectible standpoint these are really rugs to be used and enjoyed.