Page 194 - Copper and Bronze in Art: Corrosion, Colorants, Getty Museum Conservation, By David Scott

P L A T E 8 Head of the Emperor Hadrian, Roman,
second century . E . Bronze, : 39 cm. Found in the
C
H
river Thames at London Bridge, this head was once
part of a colossal hollow statue. Shown after conserva­ 10
tion cleaning, it is an excellent example of a well-
preserved cuprite patina. Collections of the British
Museum, London.
P L A T E 9 Statuette of the God Horus with Lion-
Headed Aspect, Egyptian, ca. 690-52 5 B . C . E . Bronze.
H : 67 cm; w: 17.5 cm; D : 32.5 cm. This cast-bronze
figure illustrates a well-developed cuprite patina pre­
serving surface detail. Collections of the Shumei Cul­
tural Foundation, Shigaraki, Shiga, Japan ( SF2-048) .

P L A T E ίο Photomicrograph of a typical bronze
patina on a British Bronze Age palstave from Kent,
ca. looo B . C . E . The cross section shows sound
metal below yellow and red cuprite layers and a
malachite crust with soil minerals above. The jagged,
dark particles represent the remaining uncorroded
alpha+delta eutectoid phase of the bronze (89% cop­
per, 8% tin, o.5% arsenic). Viewed under crossed
polars (unetched, magnification x325).

i
P L A T E l Photomicrograph of a Chinese bronze 11
buckle from the Han dynasty (206 B . C . E . - 2 2 0 C . E . ) ,
showing the pseudomorphic dendritic remnant struc­
ture of the original bronze casting to be exceptionally
well preserved entirely in cuprite. Patterning in
the outer corrosion layer as well indicates the pseudo­
morphic structure continuing into the malachite.
The sample was viewed under crossed polars
(unetched, magnification x435). Private collection,
London.

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