Natural Science in Archaeology

7.5 Other Copper Minerals 165
in the sandstone formation at Timna, from approximately 1300–1100 BCE. In the
second century CE, the Romans had a small mining operation there. The first copper
“beads” from the Near East may have come from rare native copper nuggets but,
just as likely, may have come from accidental smelting of malachite or azurite in the
Neolithic campfires, or from the reduction of malachite or azurite “paint” on early
pottery.
During the Pre-Pottery Neolithic B, people moved into the southern Sinai to
exploit deposits of malachite, turquoise, and flint. The flint industries left behind a
very large number of stone tools and flakes. Turquoise was mined in the Maghara
area. Long-lived settlements were formed in the location of the malachite deposits.
The malachite was used only for ornaments, pigments or cosmetics, as smelting in
this region dates to the later Bronze Age (Rothenberg 1979).
Malachite and chrysocolla ores emplaced in a dolomite-limestone-shale host
rock have been mined since the Early Bronze Age at Feinan in the Arabah Valley of
southern Jordan. In the Chalcolithic, the miners extracted malachite and other copper
minerals from sandstone at Feinan (Hauptman et al. 1992).
Azurite, Cu 3 (CO 3 ) 2 (OH) 2 , is a deep blue complex copper hydroxycarbonate
related to malachite, but less abundant. The name comes from the Persian word
lazhward meaning blue. Azurite was an early, easily smelted ore of copper. It forms
in the upper oxidized zone of copper sulfide deposits along with the more common
malachite. Azurite has a long history of use and was used as a cosmetic by the
Egyptians. However, once powdered, it absorbs moisture and over time will lose
its blue color and become green. The deposit at Chessy, France, was worked in the
Bronze Age and in Roman times.
Chrysocolla, (Cu,Al) 2 H 2 Si 2 O 5 (OH) 4 ·nH 2 O, is a complex hydrated silicate of
copper. It was named by Theophrastus by combining two Greek words for gold and
glue, because it looked similar to a material used to solder gold. Sense (1966) has
reported a prehistoric, possibly Hohokam, chrysocolla quarry at Ray, Arizona. The
ancient miners removed over 180 tons of rock in quarrying the chrysocolla. Stone
tools were recovered at the site.
Chalcopyrite, CuFeS 2 , is the most widely occurring ore of copper. It is easily
recognized by its brass-yellow color. Although pyrite is called “fools’ gold”, chalcopyrite
has a much more golden color than pyrite. The development of copper sulfide
metallurgy – more complex than copper oxide metallurgy – allowed the continued
expansion of bronze-making in the ancient world. Sulfide ores in copper deposits lie
below the oxidized ores, so ancient metallurgists may have been forced into sulfide
smelting when the oxide ores were depleted.
Cupiferous Pyrite FeS 2 . In two of the great ancient copper mining areas of
antiquity, Cyprus and Spain, the primary copper mineral was cupiferous pyrite. The
great copper-pyrite ore bodies of Rio Tinto in southern Spain have been exploited
since Phoenician times. The ores are dominantly massive pyrite, containing between
2% and 12% copper. These deposits are capped by a gossan more than 25 m thick.
Another pyrite deposit that has been mined for copper (and lead) since at least the
tenth century is the Rammelsberg deposit, which lies on the northern slope of the
Harz Mountains in Germany.