Phil Bell Antique Rugs has dated this Antique Ningxia Wool Rug to the 1850s.
I am no expert on Chinese rugs but when I venture outside of my comfort zone I search for anything that has a look and this rug certainly meets that criteria.

Very low pile to the central field with foundation showing. The ends are a little untidy and have lost some rows of knots as is to be expected on a piece of this age. There is a small hole repair visible in the photographs.
Phil Bell Antique Rugs has dated this Antique Ningxia Wool Rug to the 1850s.
You can view the stock and full dealer information on the Phil Bell Antique Rugs Profile Page