I also examined the marking under the vase using a high powered lens. I was able to obtain the same image that appeared on Christies' website. Based upon this information it appears to be the work of Wang Bu or possibly another well known artist from the Jingdezhen Kiln!!! This is an absolutely fine antique piece.
It is a magnificent cobalt blue and white Chinese glazed porcelain Prunus baluster vase. The background is in a deep rich cobalt blue color with white cherry blossom flowers, and cherry branches throughout.It has a fluted top and bottom. The vase is in excellent condition and is marked/signed with a Jingdezhen mark on the bottom of the base. The height of the vase is 18" and the diameter is 8" and weighs 6.5 pounds. This item is in the category "Antiques\Asian Antiques\China\Vases". The seller is "arle_gros" and is located in this country: US.
This item can be shipped worldwide.