Page 121 - Copper and Bronze in Art: Corrosion, Colorants, Getty Museum Conservation, By David Scott

beads have been found in a late Bronze Age jewelry workshop in Greece, but Ogden notes that
later Greek or Roman use of the mineral in jewelry is rare.
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In South America, malachite and turquoise were commonly used as an inlay n pre-
Hispanic metal objects, especially in ancient Peru during the Moche, Recuay, or Chimu cultures
from the early centuries of the common era. The decorative use of these minerals extended into
the Inca period up to 1450. Malachite is also used as a veneer on the doors of the Chapultepec
Palace in Mexico City.
Malachite continues to be used in contemporary jewelry, often polished into cabochons or
carved for use as flat brooches or pendants (Newman 1987).

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Malachite as Malachite was valued primarily as a copper ore n ancient
a copper ore Egypt, where there is evidence for the beginnings of copper
smelting as early as the fourth millennium B.C.E. At around the
same time, copper smelting was becoming an important technology in Babylon. In China, mala­
chite was probably mined for copper ore quite early on as well. During the Tang dynasty
(6I8-907) it was mined in Daizhou in northern Shanxi province and, by the eleventh century,
from Xinzhou in eastern Jiangxi province.
The Sinai peninsula was an important source of malachite n ancient times. The ore
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was found in the form of nodules within veins in the rock. Rothenberg (1990) carried out
detailed surveys and excavations of mining locales at Timna and elsewhere in the Arabah
region of the Sinai.
Malachite, mixed with either quartz or iron oxides as flux, depending on the nature of the
gangue minerals (impurities), is relatively easy to smelt with charcoal to produce metallic cop­
per. Early Bronze Age bowl furnaces often produced a mixture of sintered minerals together
with copper prills. To extract the prills, the unreacted malachite (or other copper ore) and
charcoal together with slag would be broken up and crushed, allowing the copper prills to
be extracted. These could then be combined in a crucible and smelted to produce metallic
copper. A laboratory experiment by the author showed that when a graphite crucible is filled
with crushed malachite, quartz, and charcoal, then fired at 800 °C, prills of metallic copper are
readily produced.

Nomenclature confusion Confusion about copper carbonates and copper silicates (e.g.,
chrysocolla) was common in early texts about these minerals.
The Greek physician and pharmacologist Pedanius Dioscorides (40-ca. 90 C.E.), for example,
may have been referring to malachite when he wrote:

Chrysocolla, that of Armenia is the best, very much resembling leeks in ye colour, but that
of Macedonia is ye second, then the Cyprian, and of this the pure is to be chosen.... [T]he

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