A GREEN MARBLE DREAMSTONE JIAQING PERIOD, DATED TO THE GENGWU YEAR (1810)

inscribed along the top with a poem, by Yuntai ti ('Cloud Terrace'), dated gengwu qiuri ('Autumn 1810') and three seals - top left Ruan Yuan shihua ('Ruan Yuan's Stone Picture'), bottom left Ruan Yuan Boyuan fuyin ('Ruan Yuan Boyuan, His Personal Seal'), and top right Tian Beng Lou ('Sky Splitting Tower'); hongmu stand

Ruan Yuan Collection (1764-1849).
Zeng Xianqi Collection, Boston.
Wang Jiqian (C.C. Wang), Collection, New York.
Acquired from Wang Jiqian, July 1986.

Tseng Yu-ho (Betty Ecke), Some Contemporary Elements in Classical Chinese Art, no. 17, Honolulu, 1963.

Apart from some chips on the corners, the overall condition is very good.
"In response to your inquiry, we are pleased to provide you with a general report of the condition of the property described above. Since we are not professional conservators or restorers, we urge you to consult with a restorer or conservator of your choice who will be better able to provide a detailed, professional report. Prospective buyers should inspect each lot to satisfy themselves as to condition and must understand that any statement made by Sotheby's is merely a subjective, qualified opinion. Prospective buyers should also refer to any Important Notices regarding this sale, which are printed in the Sale Catalogue.
NOTWITHSTANDING THIS REPORT OR ANY DISCUSSIONS CONCERNING A LOT, ALL LOTS ARE OFFERED AND SOLD AS IS" IN ACCORDANCE WITH THE CONDITIONS OF BUSINESS PRINTED IN THE SALE CATALOGUE."

The inscriptions on the dreamstone read:

A Huafu ('Painting')

Shuiyun liuhuang shangen fan
Lu guaishi ruxin tianran

On a sheen of water, yellowish brown,
        mountains float on their roots,
In green strange stone as natural,
        as ever could be wished.

Inscribed:

Gengwu qiuri ('Autumn Day in the Gengwu year' [31st July - 27th October 1810])

Yuntai ti ('Inscribed by Cloud Terrace').  (The 'Cloud Terrace' was the hao of Ruan Yuan).

Seals:

Ruan Yuan shihua ('Ruan Yuan's Stone Picture')
Ruan Yuan Boyuan fuyin ('Ruan Yuan, Boyuan, His Personal Seal')
Tian Beng Lou ('Sky Splitting Tower')

The last seal appears to be the name of the picture and not an actual studio name.

Ruan Yuan (1764-1849) was a scholar-official during the late Qianlong - Daoguang period.  He passed his jinshi exam in 1789 and was subsequently appointed to the Hanlin Academy.  His most noted work was the Biographies of Astronomers and Mathematicians. 

Aside from being a fervent scholar widely researching and publishing papers on Qing history and Chinese classics and being an assiduous official with numerous postings throughout China, Ruan Yuan was also well known for being an antiquarian.  He wrote several volumes on inscriptions on ancient bronzes and stones.  At one time he owned more than 460 bronze pieces in his own collection. 

He was also greatly interested in the art of cutting marbles of different shades to represent paintings, shihua ('stone picture').  He left a work describing these 'pictures' in his possession entitled Shihua ji, 5 juan, printed in the Xuehai tang zongke.  According to Betty Ecke, the present lot was one of four dreamstones owned by Ruan Yuan.