Page 200 - Copper and Bronze in Art: Corrosion, Colorants, Getty Museum Conservation, By David Scott

P L A T E 19 Fang lei (wine vessel), Eastern Zhou
dynasty (770-221 B . C . E . ) . Bronze with copper
and malachite inlays, : 31.8 cm. The surface
H
decoration, based on an ancient Chinese cloud- 2 0 Δ
and-thunder motif, was produced with a primary
inlay of copper strips set into precast recesses,
which were then used as the framework for
the inlays of malachite. Originally, there would
have been a contrast in colors between the
golden bronze, reddish copper, and green of the
malachite, but after corrosion of the bronze,
a malachite patina developed, resulting in a very
subtle gradation in color among the three surface
components. The Shinji Shumeikai Collection,
Kyoto, Japan (ss 1223).

P L A T E 2 0 Two views of malachite crystals
from the corrosion crust of a Greek box mirror
(see F I G U R E 1.2): A , plane polarized view; and
Β, polarized view, in which the fibrous character
of the malachite can be seen (both at magnifi­
cation X1035). In the plane polarized view, the
malachite is often slightly fibrous in appearance
and also shows internal detail due to cleavage 20R
planes; small malachite particles (< 5 μιη) may
be almost colorless, but larger ones are usually
green. In the polarized view, birefringence is
often high enough for first-order red or second-
order blue to appear under crossed polars.

P L A T E 21 Photomicrograph of the surface of
the Roman bronze statue of Roma or Virtus (see
P L A T E 71) showing fibrous malachite occurring
as curled crystals. These crystals are unusual
in their luxuriant growth and could easily be
x
mistaken for textile fibers (magnification 8o).

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