Archaeology Magazine - September/October 1983 - 40

ognized. This vein extended outward from the Cerro
Blanco stock and was originally about three meters wide at the surface where it cropped out of the
older rock formation. Prom its point of emergence
it ran downhill for some 17 meters. Prehistoric miners
carefully followed its course, leaving a narrow, long,
open trench. A short distance into the hillside
the miners encountered another and much larger
highly mineralized vein that intersected the discovery
vein at right angles. It was this second vein that
apparently provided much of the ore used at Cerro de
los Cementerios. This steeply plunging ore body was
worked at its highest level by the prehistoric miners,
while Colonial and modern miners excavated vertical shafts into three deeper levels of the same vein.
In well-preserved prehistoric prospecting pits we
found various large triangular hammerstones as
evidence of mining activity. These stones are typically
about 20 centimeters long and ten to 12 centimeters
wide, and would have been haf ted or held with both
hands. The stones themselves are battered, as are
the walls of the narrow crevice-like pits into which the
miners squirmed. Indeed, the stones recovered at
Cerro Blanco are remarkably similar to those found in
association with the celebrated "Copper Man/' a
prehistoric miner who died and was preserved in a collapsed copper mine at Chuquicamata in the Atacama Desert of north Chile. This miner was found
with four haf ted stone hammers, five wooden
wedges, one hafted spade with a stone blade, a wooden
spade, a hide bag, and four coiled baskets- in all
likelihood the same sort of equipment used by the
miners at Cerro Blanco.
Although much ore has been removed over the
centuries from the Cerro Blanco mine, analysis
indicates that it was a complex of copper-lead-zinc
oxides and sulfides. It was probably sorted and
crushed near the mine to minimize the burden of
transport. Llamas- which can carry up to 100 pounds
of cargo- were most likely used to carry the ore
to the smelting site.
^3asically, then, a local oxide ore was mainly used
in charging the furnaces at Cerro de los Cementerios.
The smelting process itself was a surprisingly complex one involving the careful coordination of a
whole host of activities- blending the original charge
for the furnace, which included charcoal and a fluxing material as well as the ore; regulating of temperature; and constructing, maintaining and attendj
ing the furnaces.
The site has been divided into three sectors according to architectural and topographical differences. The smelting area at the northwest corner of
the site, corresponding to Sector III, is well situated for the procurement of the resources vital to copper production. Located close by are fine-grained
igneous rocks, either basalt or diorite, that fracture into flat-sided slabs. These slabs were ideal for
what are known as batanes- large stable anvils
with a slight concavity used for crushing slag to extract the prills. The rocking stone used in conjunction with them is known as a chunga . Sectors I (the
eastern third of the site) and III together have
yielded 43 batanes, and many other holes were left
after batanes were removed for household use in
modern times. These stones are apparently much
sought after. A survey of the Batán Grande vil40 archaeology

lage revealed 20 batanes still in use, and old-timers in
the village speak of many more that have been
carried off from the site to more distant communities
within the past 50 years.
The other ingredients necessary to charge and fire
the furnaces were also locally available. The materials used as flux, hematite and limonite, were available from a mountain four kilometers west of
Cerro Blanco. Fuel was available from the subtropical
thorny forest that covered perhaps 100 square kilometers immediately north and west of Cerro de los
Cementerios. Today, this forest still surrounds
some 50 major cemeteries and religious structures of
Batán Grande; significantly, much of the area
shows no evidence of intensive or extensive Prehispanic cultivation. The local fuel supply appears
to have remained adequate despite the fact that primitive copper smelting consumed several pounds of
charcoal fuel for each pound of ore smelted and ten or
more pounds of charcoal per pound of copper
metal produced.
The final crucial ingredient had to be brought
from a greater distance. This was the arsenic-bearing
sulfide ore that was used as an additive during the
smelting process. Not coincidentally, Cerro de los Cementerios is situated near the major prehistoric
north-south road that crosses the region. Francisco
Pizarro and his men followed an inland-bound
branch of this road in 1532 on their way to Cajamarca
in the North Peruvian highlands where the ill-fated
Inca king, Atahualpa, awaited them. This road and
its branches were undoubtedly crucial to the importation of the sulfide ore to and the exportation of
metal products from Cerro de los Cementerios.
Although small, scattered pockets of arsenical ore
probably exist on the North Coast, archaeologists
and geologists have not been able to locate any exploitable arsenical deposits large enough to have
supplied the large-scale smelting centers such as
Cerro de los Cementerios. Arsenical ores were probably imported from the North Highlands, for example, from the Hualgayoc-Sinchao mining district
north of Cajamarca or the Cascas region west of
Cajamarca, which are separated from Batán Grande
by a distance of some 120 kilometers. The ore importation that required, among other things, a longlasting economic and political agreement with
North Highland polities and the coordination of llama
caravans with the ore supply and demand, we suggest, took the form of state administered trade. The
high representation of large, adult Andean camelids
among animal remains recovered at Cerro de los
Cementerios supports the idea of llama caravans as
the principal means of ore transport.
For much of the site's three-period occupational
history (ca. A.D. 1100-1400 or Late Sicán; A.D. 14001460 to 70 or Chimú; and A.D. 1470-1532 or Inca),
Sector III was clearly the focus of large-scale
metallurgical production, although the scale, organization and range of metallurgical activities that
occurred here appear to have differed from one period
to another. In addition, various lines of evidence
argue that Sector I was the center of hammering, annealing, forging and general metalsmithing during the final period, complementing the large-scale
smelting in Sector III.
In Sector III the evidence of metallurgical
activity during the latter two periods is overwhelm-

Archaeology Magazine - September/October 1983

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