Scientific analysis of a Chinese bronze Money Tree

An ongoing project involving the Portland Art Museum (PAM) and our laboratory was initiated in February 2009. The specific goals of this project are to address the Museum's concerns about an object in their collection, a Chinese bronze Money Tree, believed to date from the Eastern Han Dynasty (25 - 220 CE). Money Trees are burial objects that have a stylized tree-like form with the possible intended purpose of providing the deceased with prosperity in the afterlife. The Portland Art Museum's Money Tree was a donated gift from a private collector and had neither documentation as to the location or date of its excavation, nor any subsequent documentation prior to its acquisition by an art dealer. Students, both at the undergraduate and graduate levels are involved in this interdisciplinary and inter-institutional project.  Their work directly addresses the PAM's interest in understanding the strength of the Tree's corroded bronze and to understand whether the individual branches of the Tree come from the same original set or whether the branches were compiled and assembled to produce a complete Tree. This work is in collaboration with the Portland Art Museum.

Yao qian shu (Money Tree),
left. 2004.114.9A-C Height: 52”; Width: 22”; Depth: 19.5”. Detail (center) shows extensive corrosion. X-Ray image (right) reveals hidden artistic details and symbols of a dragon and coins.


Stereomicroscope image (left) and X-ray image (right) of a repaired branch. X-ray Fluorescence maps (bottom row) of copper (left), lead (center) and tin (right), show that the branch was repaired using lead/tin solder and that the alloy composition of the thin tenon is different from the rest of the branch. Those findings suggest that the repair is not original to the Tree and indicate that someone repaired carefully repaired and disguised the break before the Tree was sold.


X-radiograph of branches of the PAM Money Tree.
Outcomes from this work include presentations at the 2010 AAAS Pacific division conference in Ashland, OR and at the annual meeting of the 2010 Western Association for Art Conservation in Portland, OR. This work has been featured in articles in The Oregonian and Portland Monthly Magazine. The Money Tree is back on display at the Portland Art Museum in a special exhibition titled, "Cornerstones of a Great Civilization". Dr. Lasseter Clare was invited to give a public talk at the Portland Art Museum about her findings on March 4th, 2011.