Page 333 - Copper and Bronze in Art: Corrosion, Colorants, Getty Museum Conservation, By David Scott

Notes
1 Pedanius Dioscorides De materia medica 5.91 22 Green bice (malachite) was often used from the
(Dioscorides [1933] 1968). sixteenth to the eighteenth century in synthetic
2 Since there are no entries in the I C D D files for as well as natural form.
the basic copper (II) formates, some additional 23 If too much colophony is added, the color of the
G
X-ray diffraction data were determined at the C I mixture becomes less intense.
Museum Research Laboratory to produce the set 24 Analysis by Narayan Khandekar, C I Museum
G
of data shown in A P P E N D I X D , T A B L E 9. Research Laboratory, Los Angeles, Septem­
3 Schweinfurt green is the alternate name for emer­ ber 1997.
ald green, a mixed copper acetate-copper arsenite 25 Cennino d'Andrea Cennini The Craftsman's
salt discussed later in this chapter. Handbook 56.33 (Cennini [1437] i960) .
4 Observations by the author and Kenneth Hard- 26 Herant Khanjian, letter to the author, 22 Sep­
castle, Los Angeles, June 1999. tember 1998.
5 Ashok Roy, letter to the author, 12 April 1998. 27 Kenneth Hardcastle, conversation with the author,
6 Peter Mactaggart, letter to the author, with March 1997.
samples, 6 July 1997. 28 Although this formula is given in the I C D D files, it
7 The use of grapes in the production of verdigris seems a rather strange empirical formula, and one
was mentioned by Dioscorides in his De materia wonders if it should not be ClCu(CH 3COO).
medica as early as the first century. He writes 29 John Twilley, conversation with the author,
that "hiding one mass or plate [of copper] or else 6 April 1999.
more amongst the huskes of grapes, not pressed 30 Since this formula is very similar to that of pos­
of late, but growing sour, invert it in like sort" njakite, Cu 4 S0 4 (OH) 6 -H 2 0, there is a possibility
(Dioscorides 5.91). that posnjakite is actually present. Alternatively,
8 Harley 2897, Department of Printed Books and it could be the new compound identified by
Manuscripts, the British Museum, London. Strandberg (see C H A P T E R 5).
9 Pliny the Elder Natural History 34.27 (Pliny 1979). 31 The J. Paul Getty Museum's villa site in Malibu
10 Pliny 34.26. was closed to the public in 1998, and the sculp­
11 Pliny 34.28. tures were removed in 200 0 for renovation of
12 Dioscorides 5.91, s.v. "verdigris." the villa.
13 Dioscorides 5.91. 32 Scheele anticipated Joseph Priestley's discov­
14 Pliny 34.26. ery of oxygen and made many other important
15 Presbyter Theophilus De diversis artibus, rec­ discoveries.
ipe 35 (Theophilus i96i) . 33 This is the first volume issued by the I C D D , and
16 Theophilus, recipe 36. it is surprising that a material now as obscure
17 This manuscript is discussed in C H A P T E R 1 in as emerald green would have been listed so early
connection with the plating of iron. in these files.
18 Peter Mactaggart, letter to the author, 22 Sep­ 34 Arthur Gilbert Dandridge, Hugh Albert Edward
tember 1996. Drescher, John Thomas, and Scottish Dyes Lim­
19 Alum (potassium aluminium sulfate) was also ited are named as inventors in British patent
known as alume di Roccha, which the Italian met­ 322169.
allurgist Vannoccio Biringuccio (i480-ca. 1539)
notes is probably derived from "al-Ruha," the
Arabic name for Edessa (now Urfa, Turkey)
(Partington 19 i). Arie Wallert, however, in a
6
conversation with the author, July 1997, doubted
that this was correct and stated that the "roch
alum" referred to in the recipe probably derives
from the use of rock or mineral alum, the crude
initial deposit as opposed to a purer variety, and
has nothing to do with Edessa.
20 A perennial evergreen shrub with bitter, strongly
scented leaves, used for thousands of years in
medicinal preparations.
21 O. P. Agrawal, conversation with the author,
Lucknow, India, April 1996.

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