Page 269 - Copper and Bronze in Art: Corrosion, Colorants, Getty Museum Conservation, By David Scott

Copper Silicates

CHAPTER g

copper silicate minerals are highly insoluble and are found
under widely disparate conditions. Only two of the copper silicates have relevance to the pres­
ent discussion, however: chrysocolla and cuprorivaite. Chrysocolla, which is a commonly occur­
ring mineral, is important primarily because of its use as a pigment. Cuprorivaite, which is rare,
is the mineral analog of the important synthetic pigment Egyptian blue.
Dioptase, CuSi0 3 -H 2 0, (discussed later in this chapter) has been used occasionally as an
inlay or overlay, no doubt, but there are very few reports of its occurrence. There are no reports
of the use of two other copper silicate minerals: plancheite, Cu 8 (Si 4 O n ) 2 (OH) 4 -H 2 0, and shat-
tuckite, Cu 5 (SiO s ) 4 (OH) 2 .
Some characteristics of these minerals are presented in TABLE 8.1.