A bronze fitting (mao), early Western Zhou dynasty, 11th-10th century BC. Photo: Sothebys.

the domed top cast with a whorl pattern of feathers incorporating two birds’ eyes suggesting a stylized bird motif, the sides finely cast in low relief with two confronted birds with bulging eyes and a wide tail arching forward on a leiwen ground, the diamond-shaped punctures originally with inlays, all covered with dark silver patina and malachite encrustation. Height 2 7/8  in., 7.3 cm. Estimation 80,000 — 100,000 USD

Provenance: Collection of Bernard Berenson, Florence.
Collection of Adolphe Stoclet, Brussels.
Eskenazi Ltd., London, 1975.
The British Rail Pension Fund.
Sotheby's London, 12th December 1989, lot 18.
Eskenazi Ltd., London, 6th July 1990.
Sze Yuan Tang Collection.
Christie's New York, 16th September 2010, lot 821.

Exposition: Ancient Chinese bronzes from the Stoclet and Wessen collections, Eskenazi Ltd., London, 1975, cat. no. 5.
The Glorious Traditions of Chinese Bronzes, Asian Civilisations Museum, Singapore, 2000, cat. no. 30.
Metal, Wood, Water, Fire and Earth – Gems of Antiquities Collections of Hong Kong(Chinese Archaic Bronzes), Hong Kong Museum of Art, 2002-2006.

Litterature: Otto Kümmel, Jörg Trübner zum Gedächtnis, Berlin, 1930, pl. 22 (b and c).
H.F.E. Visser, Asiatic Art in Private Collections of Holland and Belgium, New York, 1948, p. 157, pl. 38, no. 43.
Li Xueqin, The Glorious Traditions of Chinese Bronzes, Singapore, 2000, p. 96, no. 30

Notes: This finely embellished bronze fitting was reportedly the only archaic Chinese bronze in the collection of Bernard Berenson (1865-1959), the renowned historian of Renaissance art and advisor to major collectors in the early 20th century. 

A similar example, excavated from Zhuyuangou village, Baoji city is discussed and illustrated in Baoji Yuguo mudi (Tombs of the Yu State in Baoji), Beijing, 1988, pp.  71-73, pl. XXVI, where the archeologists Lu Lianchen and Hu Zhisheng suggest that a bronze fitting of this kind is the bottom section of a mao, a scepter-like symbol of power and authority used by the military in ancient China. It is significant that the Baoji piece was buried alongside bronze ritual vessels on a lacquer altar in the largest tomb in the Zhuyuangou site; compare also bronze chariot fittings of slightly different form, excavated from a Western Zhou tomb illustrated in Zhangjiapo Xi Zhou mudi(The Western Zhou tombs in Zhangjiapo), Beijing, 1999, p. 207.

Sotheby's. Magnificent Ritual Bronzes – Property from the Collection of Julius Eberhardt. New York | 17 sept. 2013 - http://www.sothebys.com