Sican Archaeological Project
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ACKNOWLEDGEMENTS: The Sican Archaeological Project since its inception in 1978 has received research grants from the Heinz Family Foundation (1999), National Geographic Society (1981-83, 1985-86, 1989, 1999, 2001), National Science Foundation (1979-81, 1983-84, 1989) Shibusawa Ethnological Foundation (1990-97), Southern Illiniois University (2000), Tokyo Broadcasting System (2006-07), and Wenner-Gren Anthropological Foundation (2001-02). Our indebtedness for their generous support is hereby acknowledged.

Research Accomplishment of the SAP

To date, the SAP has conducted 24 seasons of fieldwork over the past 30 years, excavating at 15 sites of varied size, period and character, mostly in the Batán Grande-Poma area. Many sites were excavated over a span of various seasons. Our surveys have taken us as far north as the Piura valley and as far south as the Jequetepeque valley. Six seasons were dedicated to laboratory work (including artifact conservation). Over 30 specialists and 50 undergraduate and graduate students representing diverse disciplines (e.g., archaeology, art history, chemistry, electrical engineering, history, material sciences, mineralogy, and physical anthropology, among others) and countries (Cuba, England, Germany, Hungary, Japan, Peru, Spain, and U.S.A.) have participated in our project. Nearly 100 professional publications and 14 theses (doctoral, master and bachelor) written in English, German, Japanese and Spanish have resulted from our project. Below is a summary description of major achievements of the SAP to date.

A. Regional Chronology and Paleoenvironment

Figure 1: Sican Single-Spout Bottle SeriationThe SAP's effort to establish a comprehensive regional chronology focused on a series of stratified sites, particularly Huaca del Pueblo Batán Grande (HPBG) within the modern town of Batán Grande. Three seasons of excavation at HPBG (1979, 1982, 1983), a roughly conical mound (ca. 5 m high and 50 m in diameter) provided the backbone of the regional chronology. These excavations documented over 40 occupational surfaces spanning some 1500 years from Moche IV (ca. A.D. 500) to the Inka period and onto the modern era. The site not only had a textbook stratigraphy, but also numerous firepits and hearths that offered good quality charcoal and baked clay samples for radiocarbon and archaeomagnetic dating. In fact, these samples formed the backbone of the existing master archaeomagnetic sequence for Peru. The emerging chronology based on the HPBG data was tested and refined through excavations at other stratified sites such as Huaca Soledad Mound I and Huaca La Merced Mound II, both in Poma. In addition, diagnostic sherds and funerary vessels recovered from HPBG allowed us to seriate mold-made bottles and bowls, as well as paleteada (paddle-decorated) vessels (Cleland and Shimada 1992, 1994, 1998). As a result, shapes and the relative ratios of the Sicán bottle spout, body and/or base can be used for reliable relative dating. This represents the first time that paleteada ceramics have been properly seriated. The widespread use of paddled representational motifs on the northern north coast now can be securely dated to Middle Sicán (A.D. 900-1100). Overall, today, with well over 100 radiocarbon dates and two dozen archaeomagnetic dates for 15 sites, the Batán Grande-Poma area is one of the best dated areas of South America.

As part of regional chronology building, the SAP excavated (1979-1982) the Temple of the Columns (ca. 1100-700 B.C.), a two-tiered, U-shaped ceremonial platform, at Huaca Lucía-Chólope in Poma (Shimada 1982, 1986; Shimada et al. 1982). The architecture distinguished itself for its monumental features, including 24 regularly spaced, adobe-mortar columns measuring ca. 1.2 m in diameter and with an estimated original height of 4 m. However, it was the ritual entombment of the platform that was most notable. The entire platform, including the columns, was carefully and thoroughly buried by three successive layers of sealed clean sand totaling 8 meters. Evidence of similar intentional burials of ceremonial structures of the same time period was subsequently reported for various sites farther south along the Peruvian coast (e.g., Samaniego et al. 1985). In Poma this local tradition of the ritual entombment of ceremonial architecture clearly persisted right up to the time of Spanish Conquest, but was largely lost elsewhere in the Andes by the time the Wari established its empire ca. A.D. 700-800.

Some 30 sites in Poma we have examined revealed the presence of Chólope period occupation. The 1989 excavation of a Chólope period ceramic production center with numerous small kilns (estimated to have been well over 100) at the bottom of the abandoned Poma Canal, indicates that the notable economic and religious importance of Poma had been established by 1000 B.C. This represents the earliest and the largest concentration of prehispanic kilns documented thus far in the New World (Shimada 1997a). A series of replicative ceramic firing experiments was conducted in collaboration with Peruvian potters and Ursel Wagner, a German chemist. Chemical and physical analyses of kiln lining, local clays, and sherd samples by Wagner and her team in Germany demonstrated that these 3000-year old kilns were well designed and efficient (Shimada et al. 1994, 1998; Wagner et al. 1994a, b, 1998). Results of the analyses have allowed us for the first time in Andean archaeology to reconstruct details of the conditions and temperatures of prehispanic ceramic firing. Subsequent, complementary study of Middle Sicán pottery production at the multi-craft workshop of Huaca Sialupe is described below.

In general, our surveys and excavations at numerous sites showed that human occupation in the Poma-Batán Grande area goes back to at least to ca. 2000 B.C. Sicán occupations were underlain by those of earlier cultures including the Chólope (contemporaneous with the Cupisnique), Gallinazo, and Mochica (e.g., Shimada 1981, 1990b, 1994a; Shimada and Maguiña 1994).

B. Technology and Craft Production

One of the main foci of the SAP during its first years has been an interdisciplinary investigation of Sicán technology and craft production. A notable feature of the Batán Grande-Poma area is the ubiquitous presence of metallurgical remains including impressive quantities of metal objects looted from local graves. The name of the modern town of Batán Grande derives from the numerous prehispanic batanes nearby. These are large stone anvils used together with heavy rocking stones called chungos to grind ore and slag. During his 1978 survey, Shimada had noted an ancient road connecting Cerro Huaringa, a suspected metallurgical center, to the nearby prehispanic mine at Cerro Blanco and hypothesized the presence of an important prehispanic metallurgical tradition in this area.

He recognized both the potential importance of metallurgical production to the development of the Sicán culture and the singular research opportunity offered by a wide range of well-preserved metallurgical remains, and set out to achieve a "holistic" understanding of Sicán metallurgy. The term holistic is used in various senses. In one sense, it implies a reconstruction of the technology and organization of the entire production process and definition of the meanings and roles of metal products within the culture, as well as social identity and relationships of the people involved in mining, smelting, and metalworking (e.g., Shimada 1985, 1994b; Shimada and Wagner 2001, 2007). Research has entailed investigation of mines, ores and fuels, excavation of smelting and metalworking workshops, as well as understanding of the mundane and ritual use of metal products (Merkel et al 1994). It also examines relationships between base and precious metals, and between metal and non-metal artifacts (Shimada et al. 1999, 2000; Shimada and Griffin 2005). The holistic approach is also taken to imply an integrated understanding of the full range of the metals and craft goods which were produced and used by means of archaeometry, experimentation, excavation and ethnoarchaeology.

Excavations at Cerro Huaringa (1979-1983) and nearby Cerro Sajino (1983) and HPBG (1982-83) yielded ample evidence of the intensive smelting of arsenical copper beginning in the early Middle Sicán (ca. A.D. 900) and persisting into the period of Chimú and Inka domination during the 15th and 16th centuries (e.g., Epstein and Shimada 1984; Shimada 1985, 1994b; Shimada et al. 1982, 1983; Shimada and Merkel 1991). It became apparent that, starting ca. A.D. 900, arsenical copper permanently replaced copper as the utilitarian metal of northern Peru, bringing the "bronze age" to this whole area. Even stone and bone tools were gradually replaced by bronze implements. Arsenical copper had a yellowish-silvery color and possessed superior hardness, malleability and casting ability just like the better known copper-tin bronzes. Though precious metals tend to attract more public attention, within the history of prehispanic New World technology, the successful, large scale production of arsenical copper was what distinguished Sicán metallurgy.

Thus far, the SAP has excavated four well-preserved smelting workshops and three metalworking workshops in the Lambayeque region, in addition to surveying a half dozen prehispanic mines and other inferred Middle and Late (A.D. 1100-1400) Sicán smelting sites. We suspect that there are many other metallurgical sites and mines to be found in this region. Further, it is believed that there was no one "principal" smelting center or mine, but rather regional metallurgical production built on dispersed mines and clusters of workshops, each equipped with a set of 3 to 5 small furnaces and batán-chungo sets. Lacking bellows, draft was supplied by means of blowtubes and human lung power. This inefficient technology did not achieve and sustain sufficiently high temperatures to allow smelted metal to flow and directly form usable, homogenous ingots. Rather, it produced heterogeneous spherical bits of metal called prills which were too small to be directly used and had to be remelted to consolidate into ingots.

Figure 2: Flow DiagramThe information presented here was derived from a methodology that included step-wise archaeometric analysis, replicative field and laboratory experiments, and stylistic, iconographic and contextual analysis of metal artifacts. A wide array of analytical techniques (e.g., scanning electron microscopy, neutron activation analysis, electron probe microanalysis, proton-induced x-ray analysis, x-ray florescence, and x-ray diffraction) were employed (e.g., Bezúr 2003; Gordus and Shimada 1995; Gordus et al. 1996; Merkel et al. 1994; Shimada et al. 2000). Data from the above analyses were incorporated in the design of a series of replicative experiments. Analyses of the resulting products, in turn, assisted in further refining metallurgical models. In regard to the arsenical copper smelting technology, experiments by J. Merkel, I. Shimada and Stephen Epstein first used a full-scale replica furnace, followed by a well-preserved 600-year old prehispanic furnace (Shimada and Merkel 1991). Copper oxide ore from the prehispanic Cerro Blanco mine was used for all experimental runs. It is in this manner that the above model of Sicán smelting technology was verified.

In addition, our excavations of the Middle Sicán smelting workshops at HPBG demonstrated that Sicán smelting in its early stages apparently had magico-religious aspects much like the alchemy of the Medieval Ages in Europe or primitive iron smelting in Africa that continues to this day. Construction of the furnaces was preceded by elaborate rituals and offerings (e.g., llama fetuses). At the time of abandonment, they received further offerings (food in ceramic vessels). After all, the smelting process involved a metamorphosis of naturally occurring ores into a totally distinct, valuable, "new" substance called metal.

Holistic investigation also shed important new light on long standing debate surrounding the nature of the smelting charge (i.e., whether or not sulfide ores were used) and provenience of ores (local or imported [highlands]; see e.g., Lechtman 1976, 1979, 1991). Our analysis of ore samples from excavated smelting workshops and discovered local mines showed that Middle Sicán metallurgists deliberately and directly mixed locally available malachite and oxidized forms of arsenopyrite such as scorodite to produce arsenical copper (Merkel et al. 1994; Shimada and Merkel 1991).

Arsenical copper products were not all utilitarian tools. Their products included what may well have been primitive currencies of standardized size and shape that have been found throughout much of the Middle Sicán territory and even on the Ecuadorian coast. They are believed to have been used in long-distance trade to acquire exotic goods (e.g., Spondylus and Conus shells, amber, and emeralds) from Ecuador and Colombia (e.g., Shimada 1985, 1990b; Shimada et al. 1997). The hypothesis that the Middle Sicán polity produced and used these currencies may well explain much of the political power and economic wealth inferred from grave goods.

Overall, our sustained, interdisciplinary research into Sicán copper alloy metallurgy has, for first time in New World archaeology, achieved a comprehensive understanding of a prehispanic metallurgical technology and production. Insights from our study dealing with the trajectory of technological developments and their broader social and environmental impact can be compared with those in other parts of the world, such as the transition between copper-arsenical and copper-tin-copper bronzes in the ancient Near East.

Sicán metalworkers also excelled in goldsmithing and produced precious metal objects for diverse uses at an unprecedented scale. The ongoing effort toward a holistic understanding of Sicán metallurgy was expanded to encompass these objects that are derived from elite tombs. The methodology developed for arsenical copper research was applied to this new task. For example, the effort to elucidate relationships between alloy composition and its mechanical properties and workability, as well as the inferred functions and symbolism of objects involved close collaboration among Adon Gordus, an American chemist, late Jo Ann Griffin, an American goldsmith and conservator, John F. Merkel, an American metallurgist and conservator, and I. Shimada.

Their collaborative studies (e.g., Gordus and Shimada 1995; Merkel et al. 1994, 1995; Shimada and Griffin 2005) revealed that: (1) essentially all of the well over 1,000 samples taken from precious metal artifacts from the East and West tombs at Huaca Loro (see below) are alloys of gold, silver, and copper, ranging from 18 to 2 karats; (2) each type of metal object, such as bangles, crown ornaments, and ear spools had its own relatively consistent alloy content. These studies have shown the impressive sophistication of Sicán goldsmiths in alloying. To manufacture a wide variety of ornaments and ritual paraphernalia, they produced a corresponding wide range of gold-silver-copper alloys. Each alloy offered different mechanical properties, allowing them to effectively produce desired effects or overcome manufacturing difficulties. The studies also show that, in general, the quality of metal (i.e., proportions of precious metals) in the excavated Sicán objects varied in accordance with the complexity, difficulty, and innovative character of manufacturing techniques employed and iconographic details.

Another important Sicán technology, mold-based ceramic production, has been scrutinized through the same sort of sustained, interdisciplinary investigation. Besides the aforementioned paddle-decorated ceramics, Middle Sicán ceramics distinguish themselves by being mold-made and having a fine black finish from well-controlled reduction firing. Though reduction-fired gray and black ceramics have appeared at different times starting as early as the Early Horizon, uniformly black vessels were generally not produced in large numbers until Middle Sicán times. Further, there has been a widespread tendency among archaeologists to identify any late prehispanic reduction-fired ceramics on the Peruvian coast as Chimú. Thus, U. Wagner and her team and Shimada have worked to define the technology of Middle Sicán reduction firing to differentiate Middle Sicán and Chimú gray and black ceramics (Shimada and Wagner 2001). Thus far, this collaboration has involved neutron activation analysis of Middle Sicán and Chimú sherds for chemical characterization of their pastes, Mössbauer spectroscopy for defining firing conditions and temperatures, firing experiments to replicate the original firing processes and test our models, and excavation of a Middle Sicán ceramic-metal workshop. The last was conducted during the summers of 1999 and 2001 at the site of Huaca Sialupe northwest of the town of Lambayeque and 22 km SW of the Sicán capital of Sicán.

Our research at the Huaca Sialupe workshop constitutes a good example of what Shimada refers to as a “holistic study of craft production” (see above; Shimada and Wagner 2007). It allowed us to elucidate both material and human dimensions of much of the Middle Sicán mold-based fine pottery production process (particularly the famous blackware pottery) and, to a lesser extent, the copper- and gold-alloy metalworking process. In addition, in contrast to earlier archaeological studies of craft production that have narrowly focused on a single craft without considering how it may relate to other crafts, our investigation focused on multi-crafting and multi-craft interaction within the workshop. This study also served as a test case for the political economy perspective of craft production that tends to over-emphasize the needs and preferences of elite sponsors or consumers without due attention to the role of artisans in and the consensual approach to production.

Figure 3: Ceramic Molds from the Huaca Sialupe WorkshopThe site of Huaca Sialupe consists of five small, low mounds (I-V) that together cover a roughly rectangular area ca. 250 m x 400 m. Our excavations focused on Mounds I and II. Ceramic production debris, notably broken ceramic molds and black pottery of diagnostic Middle Sicán form and/or decoration, was concentrated in Mound I (ca. 70 m across and 6 m high). Our broad excavations together exposed 480 m2 (16 x 30 m) and 115 m2 (10 x 11.5 m) of continuous area of the workshop at Mounds I and II, respectively. Together, these figures represent ca. 40% of the preserved remains of the workshop. The workshop went through many minor and at least two major remodels since its establishment ca. 950 CE. The Middle Sicán occupation is subdivided into three phases. Middle phase “B”, the best-known phase, subsumes the occupation immediately before and during a severe El Niño event (what has been called the “Naymlap flood”) dated ca. 1050 CE3. The associated torrential rains not only damaged quincha (aka wattle and daub) constructions but appear to have occasioned temporary abandonment of the workshop. A wide variety of production-related items were left on the floor.

Evidence is clear that during much of, if not the entire, span of Middle Sicán occupation, the workshop was engaged in production of molded ceramic vessels and, perhaps to a lesser extent, smithing of copper-arsenic alloys and gold alloys.

Figure 4: Middle Sican Mold-made Ceramic ProductionThe central sector of the workshop provided rooms for four major functions: (1) the formation, finishing and perhaps drying and storage of ceramic vessels in the west side rooms, (2-3) cutting, shaping and assembly of small metal objects and making of molds for appliqué and other small ornamental pieces in the east side rooms, and (4) meeting with supervisor(s) and/or resting in the rooms. This characterization is based on the documented differential distribution of diverse ceramic production and metalworking debris and tools, including prepared clay lumps, used hematite lumps (pigments), potter’s plates, scraper-shapers (made of sherds), two clusters of unfired vessels, 100 “models” or “positives” (from which multiple molds are made) and over 2000 whole and fragmentary molds. Vessel forms represented in recovered molds agree well with the over 25,000 excavated wasters and are dominated by relatively small decorated ceramics, especially stirrup-spout, and single- and double-spout bottles, face-neck jars, canteens, and shallow and deep bowls (Taylor 2002; Rospigliosi 2007).

Phase B ceramic production in the Sialupe workshop had a “modular” organization of production. This involved largely self-contained artisans or groups of artisans each working in close proximity but largely independent of each other to produce a similar or essentially identical array of products. The same artisans were involved in much, if not the entirety, of the production process.

Furnaces found in Phase A and B rooms were associated with copper-arsenic and gold alloy sheet scraps, spills, re-melting slag, and ingot molds, among other production remains, suggesting that they were utilized for forming ingots, melting scraps for recycling, and repeated cycles of annealing and forging for making sheet metal (Shimada et al. 2003a, in press). Evidence of sheet metal cutting and shaping such as chisels and sheet scraps, as well as finished needles and a spoon along with its ceramic template were concentrated in adjacent, easily accessible Rooms. Highly efficient updraft furnaces in Mound II were ingeniously made of inverted, ceramic urns. Details of these furnaces are found elsewhere (Shimada and Wagner 2001, 2007; Shimada et al. in press). In essence, air entering through a 8-9 cm round hole in the body near floor level that faced the prevalent wind would have fanned the charcoal bed inside and created heat for a variety of smithing tasks, a hypothesis well-supported by our replicative field experiments (Shimada et al. 2003a).

The documented multi-craft situation and interaction at Sialupe is not surprising given that ceramic and metal production have similar pyrotechnologies and fuel requirements. Metal working at Sialupe employed a wide range of ceramic products including ingot molds, tuyeres (ceramic tip of blowtubes), crucibles, and urns for furnaces. Our study suggests pottery-metal craft interaction extended into stylistic and symbolic domains. Middle Sicán black vessels often have a distinct metallic sheen. Scanning electron microscopy and Mössbauer spectroscopy revealed that this sheen was created by graphite crystals formed on the well-burnished vessel surface by the prolonged exposure of carbon to temperatures of ca. 900°C or higher under reducing conditions (Shimada and Wagner 2001; Shimada et al. 2003b). We suggest that its sheen reflects an effort to emulate the visual effects of prestigious metal objects.

Paleoethnobotanical study of fuel remains from ceramic kilns and metalworking furnaces by David J. Goldstein (2007; Goldstein and Shimada 2007) revealed an important, unexpected form of multi-craft interaction. Unconsumed fuel found inside excavated ceramic kilns was pure hardwood, overwhelmingly indigenous resin-rich algarrobo, Prosopis pallida, while in metalworking furnaces we found a mixture of hardwood charcoal and refuse or low quality fuel (e.g., maize cobs, canes, and twigs). Given that our black pottery firing experiments (reduction firing) conducted in 2000 yielded substantial quantities of unconsumed, hardwood charcoal of algarrobo at the end of firing, Goldstein suggests that in Sicán times charcoal from kilns were recycled for use in metalworking furnaces. Thus, contrary to expectations from the political economic model of craft production that would envision fuel usage as dictated by the Middle Sicán state or elite sponsors or determined by the differential value of expected products, our research suggests that the “choice” and apportionment of different fuels were based on functional needs and left in the hands of local metalworkers and potters. These groups of artisans who labored close to each other were likely to have directly negotiated with each other for mutually acceptable fuel usage rather than competed for fuels.

The semi-autonomous character of the Sialupe artisans was also indicated by the considerable stylistic and technical variability seen in models for making ceramic molds, molds and products even though the paste for both molds and resultant pottery was derived from local clay and highly homogeneous. Common vessel forms such as single- and double-spout bottles were assembled using anywhere from two to four pairs of molds. Even seemingly simple vessels such as shallow bowls with annular bases were formed in at least three different ways. A similar degree of variation is seen in stylistic details, for example in execution of the Middle Sicán hallmark icon of the Sicán Deity, and form and/or decoration of bottle stirrups.

Other important findings and insights resulting from our investigation at the Huaca Sialupe multi-craft workshop are found in various publications cited within the text.

C. The Site of Sicán and Monumental Architecture

Figure 5: Reconstructed View of the Site of SicánOur investigation of the organization and functions of the site of Sicán, the inferred Middle Sicán political and religious center, began in earnest in 1985. The site has a T-shaped area some 1.0 km north-south and 1.6 km east-west, a dozen monumental platform mounds and a large plaza (“Great Plaza”). Near the center of this T-shaped area lies a Huaca (a sacred object or place), a spire-like quartzite outcrop with polished grooves running down its sides. Interestingly, the dozen mounds and the huaca together outline a gigantic tumi (a knife with a crescent blade and rectangular handle; T-shaped).

Figure 6: The Inferred Tumi-Shaped Organization of the Site of SicánOur excavations atop and around the bases of the monumental adobe mounds indicated that they were built within the relatively short span of ca. A.D. 900-1000 for ceremonial activities. Some of the mounds (e.g., Huaca El Corte and Huaca El Moscón) are only 7 to 12 meters high and have a T-shape with a wide, centrally placed ramp giving direct access to the elongated top). Others are much bigger and a truncated pyramid in shape, having bases of ca. 100 meters to a side and ca. 25 to 35 meters in height (e.g., Huaca Loro and Huaca Rodillona).

All of them had auxiliary structures nearby, including what appear to have been storage facilities on the south side of the Huaca El Corte mound and metal workshops near Huacas Las Ventanas and Loro. Well-built adobe room complexes on the south side of Huaca Las Ventanas are believed to have been elite residences. The U-shaped architectural complexes of Huacas El Corte and Las Ventanas are perfectly aligned and together form the east-west axis of the site of Sicán. Both Huaca El Corte and Huaca Las Ventanas mounds show two major construction phases and were probably built as a pair. Their first phase constructions represent some of the earliest monumental constructions of the Middle Sicán period. Huacas Loro and La Merced mounds formed the north-south axis of the site. The truncated pyramidal structures of Huaca Rodillona and Huaca Soltillo (or Santillo) lie farther northwest away from the intersecting axes described above.

Excavations atop the mounds at Sicán have demonstrated their ceremonial function. All had a formally laid out, gradually ascending terrace complex, an impressive colonnade composed of dozens to hundreds of regularly spaced, painted columns, and surrounding walls decorated with polychrome murals of religious images. Sockets for these columns contained sacrificial burials and other offerings. In the case of Huaca Rodillona, an estimated 300 young women were sacrificed.

Our excavations showed that the bulk of the volume of these monumental mounds was achieved by superimposed lattices of contiguous, adobe brick chambers filled with a wide variety of materials (e.g., sand, llama dung, sherds, and metallurgical byproducts. Each chamber was built with mold-made adobe brick that varied in size, shape, color and texture of soil, and stamped or inscribed marks. Systematic analysis of marked adobe bricks and construction techniques has shown that Middle Sicán pyramid constructions required continuous effort by a unified labor force in contrast to the earlier Moche (aka Mochica) approach involving incremental constructions by independent labor groups (Cavallaro and Shimada 1988; Shimada 1990b, 1997b; Shimada and Cavallaro 1986). These marked bricks (over 220 distinct marks identified) are believed to have identified the sponsors of temples or other public structures rather than the makers of adobe bricks.

Excavation of the Great Plaza at the center of the site (1985, 1990, and 1997) revealed various hearths for feasts and small platforms for ritual performances, as well as stockpiles of adobe bricks presumably for repairs and new constructions. The abundance of serving dishes and food remains associated with hearths in the plaza, for example, suggest such feast occasions as the burials of deceased elite personages (Montenegro and Shimada 1998). Overall, this religious and political capital of the Middle Sicán culture had an aggregation of the monumental temples and associated formal structures unparallel on the Peruvian coast for its time period even eclipsing Pachacamac. Yet, it was not a population center; the capital with its temples, storerooms, elite residences and attached metal workshops, altars and tombs was sacred ground and appears to have had a relatively small number of elite and support residents. Settlements for the masses are found around the perimeter of the site and along the margins of the valley.

D. Mortuary Practices, Sociopolitical Organization, and Religion

Starting with a six-month long season in 1990, the SAP turned its efforts toward clarification of Sicán social organization and religion. Elaborate and rigid social differentiation in this culture has been inferred from various artistic representations, for example, of a well-dressed individual on a litter being carried by simply dressed men. Similarly, the importance of organized religion has been suggested by the pervasiveness and seemingly invariable appearance of the Sicán Deity icon. These inferences awaited testing and elaboration.

The basic strategy adopted was an interdisciplinary analysis of Sicán burials and mortuary practices. Such a reconstruction is difficult because excavated burials often do not accurately represent the prehistoric population under study. These burials over- or under-represent certain social segments in part due to grave looting which targets "elite tombs" with "valuable" goods. However, confident of gaining a sample of burials representing much of the Middle Sicán social spectrum, SAP began tomb excavation at the site of Sicán. Years of studying thousands of looted tombs provided useful information for locating unlooted tombs (e.g., Shimada 1981; Carcedo and Shimada 1985). By the end of the seven-month long 1995-6 season, the Project had excavated 14 securely dated Middle Sicán tombs containing 43 individuals of varied social status and roles, including those inferred to have been of the highest echelon.

Nine-month (1991-2) long excavation of two major Middle Sicán elite tombs at Huaca Las Ventanas and Huaca Loro represented the first scientific documentation of such tombs (e.g., Shimada 1995, 1997c; Shimada and Montenegro 1993). The former was situated in compacted sand below the south wing of the U-shaped architectural complex at Huaca Las Ventanas. The latter was located at the east corner of the juncture formed by a 150-meter long adobe platform (running north-south) abutting the north face of the Huaca Loro truncated pyramid. Both tombs were originally exposed by looters who had used a bulldozer to remove the overlying adobe constructions and deposits. Looters had destroyed much of the eastern half of the Las Ventanas tomb, while high groundwater (ca. 10 m below surface) prevented them from sacking the Huaca Loro tomb. During his 1978 survey, Shimada recognized tumbaga (low karat alloys of gold, silver and copper with copper being predominant) fragments and cinnabar paint left behind by looters at the former and ancient tool marks on the walls of the vertical shaft of the latter as indications of deep elite tombs and had recorded their locations. The 1983 El Niño flood filled in what had been left exposed by looters of these deep tombs, effectively preserving them for future study.

Excavation of large Middle Sicán elite tombs with expected gold and other sumptuary goods not only required worthwhile research objectives but also careful consideration of special artifact conservation and storage, as well as public expectations. Working in the Poma area with a long and infamous grave looting tradition entailed informing local population of crucial differences between grave looting and scientific excavation, and the "why" and "how" of tomb excavations. Starting in 1979, public lectures were annually offered at the town of Batán Grande, and occasionally in nearby towns and Chiclayo to describe the aims, emerging results and significance of our research. Public education has also involved inviting local people, including local school teachers to headquarters and excavation sites. Later, the project paying for school bus fuel, they brought hundreds of school children to see SAP excavations. In these ways, SAP has encouraged better protection of local archaeological sites and appreciation of their rich cultural heritage among local people, particularly among youth.

Integration of Peruvian archaeologists, both professional and student, and working year after year with the same local workers has also fostered mutual trust and an understanding of archaeology. A long-term agreement established in 1983 with the Especialidad de Arqueología, Departamento de Humanidades, Pontificia Universidad Católica del Perú in Lima assured continuing participation of their advanced students in our project.

In addition, in anticipation of diverse artifacts, a team of specialists for on-site as well as subsequent laboratory conservation and documentation was assembled. Those who had participated in the earlier SAP investigation of metallurgical production formed the core of the interdisciplinary team. This on-site presence of appropriate specialists allowed effective documentation, analysis and conservation of such fragile and/or corroded artifacts as painted cloth, thin tumbaga sheets, and traces of feathers. These and other artifacts and their excavation processes were documented in drawings, photos and videos.

Yet another important consideration in this tomb excavation was the depth of the watertable. It was obvious from earlier examination of looters' holes and published accounts of looted shafttombs (e.g., Pedersen 1976; Tello 1937a, b, c; Valcárcel 1938) that such tombs would be quite deep. Thus, it was necessary to wait until the watertable was more than 15 meters below surface.

The plan to excavate Middle Sicán elite tombs that began in 1978 became feasible in 1991 with the convergence of favorable physical and social conditions and generous financial support from the Shibusawa Ethnological Foundation and Tokyo Broadcasting System. The wait had its own benefits. By this time, the SAP had comprehensive knowledge of the Sicán culture, including a detailed chronology, and the local workers had become highly competent. The worrisome groundwater level had gone down to ca. 16 meters below surface. The local people had come to understand the importance of our research aims and voiced strong support for implementation of the plan. The establishment of a long-term collaborative relationship between the SAP and the Museo de la Nación, was also important in rounding out the interdisciplinary team and providing secure and ample storage and laboratory facilities for post-excavation work.

The Huaca Las Ventanas tomb had an inverted, stepped-pyramidal shape (Shimada 1995). Though it measured 15 meters to a side at the mouth, it reduced down to a 3 m square at the bottom some 12 meters below surface through a series of 4 steps or ledges. These ledges not only minimized the risk of landslides during the original tomb preparation, but also served as settings for offerings such as painted cloths, bead clusters, ceramics, llama heads and feet, arsenical copper and tumbaga objects. Additional ceramics, beads and metal objects were found at the tomb bottom. Gold objects were conspicuously absent.

The size and shape of this tomb appear to have been largely dictated by its sand matrix. The large pit size was also a function of the number of bodies interred. Three complete and at least six disturbed bodies, all in seated, cross-legged position, were recovered around the edges of the bottom. Those that could be sexed and aged all proved to be young adult women. Other than some traces of the cloth that once wrapped the bodies, there were few or no offerings directly associated with them. A central personage was not found, raising the interesting possibility that the tomb contained aclla-like female court retainers who were sacrificed and interred at the time of the death of their elite patron as described by some early colonial writings (e.g., Ramírez 1998).

Probably, the most striking feature of the tomb is the way much of its interior surface was lined with layers of painted cotton cloth. Each cloth was plastered, painted with a polychrome religious scene, and carefully pasted on very thin tumbaga sheets (Shimada 1995, 1998). These paintings provide new insights into the Sicán religion. One scroll-like painting shows the Sicán Deity with a tumi-knife and trophy head at the center flanked on each side by a series of the stylized ocean waves. At the east and west ends of the waves are the sun and the moon, respectively. Another shows the Sicán Deity with the same tumi-knife and trophy head standing under the arching body of the bicephalous mythical "sky serpent." and flanked by an opposing pair of seated mythical felines. These and other paintings excavated in another tomb in 1995-6 offer a new vision of Middle Sicán art and religious ideologies. Middle Sicán iconography appears to have resulted from a fusion of Moche and Wari religious concepts and motifs. At the same time, the Sicán Deity seems to have been omnipotent, controlling all the esteemed celestial forces and entities fundamental to life and abundance on the earth, and not just a simple personification of the moon as earlier studies have suggested (e.g., Carrion Cachot 1940; Kauffmann 1983, 1986, 1992). We must consider the distinct possibility that Middle Sicán iconography reflected various fundamental dualities (e.g., death-life, day-night) and the roles of key supernatural and earthly beings. Earlier visions were based on limited samples of religious images found on looted objects and overly influenced by coastal religious beliefs recorded during the colonial era.

The Huaca Loro tomb (known as the Huaca Loro East Tomb) was in essence a square-shaped (3 x 3 m), 12-m deep vertical shaft with the bottom portion serving as the burial chamber (e.g., Shimada 1995, 2006; Shimada et al. 2000, 2004; Shimada and Griffin 2005). There were seven niches in the four walls of the burial chamber. The chamber contained five individuals (an adult male, two young adult women, and two juveniles) and ca. 1.2 tons of diverse grave goods, over 2/3 of which, by weight, were arsenical copper, tumbaga, and high-karat gold alloy objects. Grave goods were arranged concentrically and superimposed in layers on, around, and beneath the body of a robust, male personage, some 40-50 years of age, placed at the center of the mat-lined, square floor. He wore full regalia including a large gold mask, and a pair of gold earspools and was found in a seated and inverted position.

The Huaca Loro East Tomb

Figure 7: East TombAmong notable contents of the burial chamber was a chest containing at least 24 superimposed layers of over 60 large ornaments and ritual paraphernalia (e.g., rattles, crowns, head bands, and crown ornaments), most masterfully formed of gold sheets (ca. 10 to 18 karats). Equally impressive were four large piles of tumbaga scraps with a total weight of ca. 500 kg and an average composition of ca. 13% gold, 30% silver, and 57 % copper, implying that the scrap as a whole may contain as much as 65 kg gold and 150 kg silver. Others features include 15 bundles of 489 cast arsenical copper implements (ca. 200 kg) placed along the edges of the burial chamber. Toward the center of the burial chamber were two piles each of carefully selected, extra-large Spondylus princeps and Conus fergusoni shells (totals of 179 and 141, respectively).

This tomb confirmed the widely held belief that there is great material wealth associated with Middle Sicán elite tombs. It effectively illustrated the power yielded by this Middle Sicán nobleman over material and human resources. Such power can be gauged not only by the impressive quality, quantities, and diversity of exotic, luxury goods, but also by the estimated labor that would have been required to produce and/or acquire them. The manufacture of tens of thousands of quartz, amethyst, sodalite, turquoise, fluorite, agate, amber, Spondylus and other beads alone (over 75 kg altogether) would have amounted to a tremendous labor investment. Some 500 kg of scraps of hand-hammered, uniformly thin (mostly about 0.05 to 0.1 mm) tumbaga sheet was probably generated during the course of months of work by many skilled goldsmiths and their apprentices. There were only a few objects in this tomb bearing religious motifs; rather, what predominated were repetitious representations of a Sicán Lord, earthly alter ego of the Sicán Deity. The good match between the appearance of the principal personage of the tomb and the Sicán Lord shown on these gold objects suggests that they are one and the same. For high ranking noblemen, personal glorification may have been of higher priority than glorification of the Sicán Deity.

Another Middle Sicán elite tomb, called Huaca Loro West Tomb (Shimada et al. 2004), was excavated during seven-month fieldwork in 1995-6. Ground-penetrating radar surveys conducted in collaboration with a Japanese engineer, Hirokatsu Watanabe, in 1994 and 1995, detected a series of deep pits suspected of being intact shafttombs under the outer edges of the Huaca Loro pyramid base and on the east and west sides of the 150-m long platform.

The Huaca Loro West Tomb

Figure 8: West TombThe West Tomb was symmetrically situated with respect to the East Tomb across the north-south longitudinal axis of the platform and the pyramid. Thus, its excavation was conducted to test the hypothesis that it was indeed a shafttomb and that this and the East tombs were part of the planned cemetery of a Middle Sicán elite lineage placed under and around the Huaca with the tomb of its founding ancestor at the center. A corollary hypothesis was that the north-south longitudinal axis served the symbolic role of separating deceased members of complementary moieties and that physical distance between the Huaca center and a given shafttomb reflected generational or status differences.

Excavation revealed that the West Tomb had a two-tier, nested construction. The antechamber was located 12 m below surface and measured some 10 m north-south by 6 m east-west. It featured 10 wall niches and 12 rectangular sub-floor pits. Situated at the center of the tomb was the central chamber, a 3 x 3m shaft that descended another 3 m to a depth of 15 m below the surface. Six pits each formed 2 symmetrically opposing groups on the south and north sides of the central chamber. Each pit contained one or two young adult females with textiles, ceramics, and other goods.

The central chamber appears to have been reserved for placement of the principal individual and his grave goods. This individual, a relatively robust man of ca. 30-35 years who had suffered a serious stab wound on his hip, was placed at the center of the mat-lined floor in a cross-legged, seated position. He and a young boy (? 12-13 years of age) placed in a niche in the Antechamber above looked directly at each other. The principal personage wore full regalia, including a large tumbaga mask, tumbaga and gold headdress, tumbaga gloves, and pectorals of mineral beads. He was surrounded by a diverse range of grave goods including 8 camelid heads, and the articulated feet of at least 25 camelids, both large and small forms, earthen casts of 9 rolls of narrow cloth long since perished, and 4 tumbaga sheet-covered ceramic bottles and jars, among other items. As if to flank the principal individual, a young adult female was placed in each of the symmetrically opposing niches on the north and south walls of the Central Chamber. Placed beneath the female on the north side was a rectangular chest that contained some two dozen personal ornaments made primarily of tumbaga sheets. In spite of its impressive size (some 7 times the volume of the East Tomb), complex internal structure and many bodies (24 as opposed to 5 in the East Tomb), the quantity and quality of metal goods (both precious metal and arsenical copper) in this tomb pale in comparison with those of the East Tomb.

The spatial arrangement of artifacts and human bodies in these tombs suggests possible biological, social, and/or symbolic relationships among the interred individuals within each tomb and between the two tombs (Corruccini et al. 2002a, b; Shimada et al. 2004, 2005). For example, the placement of two adult women close to the principal personage is seen in both the East and West Tombs. In the former case, it appears that the principal personage and two nearby women together formed a symbolic representation of the reincarnation of the principal personage; that the inverted burial position symbolized the fetus in the womb about to be born and that the prone position of one of the women in the burial chamber represented the act of giving birth attended by the other woman acting as mid-wife. In this interpretation, cinnabar painted on the body of the principal personage symbolized life-giving blood and the blood that accompanies birth.

Our interdisciplinary approach proved to be quite productive in exploring the significance of the symmetrical opposition created by the two groups of nine women on the north and south sides of the Antechamber in the West Tomb. That the nine women on the south side of the Antechamber may have been socially linked to the principal personage in the Central Chamber was first suggested by cloth strips that physically connected them. No comparable "linkage" by cloth strips was found in the north half of the Central Chamber. In addition, ceramics and a painted textile showing clear affiliation with the earlier Mochica style and iconography were found to be concentrated on the north side.

These indications were independently confirmed by examination of 23 inherited dental traits and measurements by Robert Corruccini, a physical anthropologist. He sought to clarify biological relationships (i.e., how closely individuals are related) of individuals excavated in the East and West Tombs as well as relationships within each group. For example, he found that the West Tomb principal personage most resembles the juvenile boy in the niche of the same tomb, while the boy in turn most resembles the two women who flanked the principal personages in the same tomb. Further, these women are most closely related to the three adults in the East Tomb. As suspected, the nine females on the south side (“South Women”) of the West Tomb are genetically quite homogeneous and are more closely related to each other than the females on the north side (“North Women”). They may reflect an endogamous situation or members of kin lineages. The females on the north side of the West Tomb are relatively quite heterogeneous among themselves and may represent unrelated (perhaps non-local) people who married into patrilocal context.

To improve our understanding of biological or kinship relationships among the excavated individuals, Kenichi Shinoda, a Japanese physical anthropologist at the National Museum of Nature and Science in Tokyo, Japan, and Shimada collected tooth samples for mitochondrial-DNA analyses. Our analysis revealed some significant genetic patterns (Shimada et al. 2004, 2005, 2006). Perhaps the most significant result is the documentation of four distinct maternal kinship ties among 12 women, and the bipartite spatial distribution of related individuals in the West Tomb. There are two sets of maternal relatives within each of the North and South Women groups. The related women were buried close to each other. In addition, the North and South Women are characterized by two mutually exclusive sets of haplotypes. In other words, the north versus south groupings of women have a kinship basis that crosscuts the Antechamber-Central Chamber division.

Figure 9: Kinship RelationshipsIt is evident that north-south division in the West Tomb reflects significant biological, cultural, lifestyle and perhaps even status differences. The relative biological proximity and homogeneity of the South Women revealed by dental trait and mtDNA analyses suggest that they practiced endogamy or at the least represent some sort of kin lineage. The cloth strip that connected the South Women and the principal personage in this regard may be seen as symbolic of their shared membership in the same lineage. It is also worth noting that the basic social organization of the late pre-Hispanic north coastal population, according to ethnohistorical accounts, was parcialidades, indigenous endogamous social groups organized by occupational speciality and asymmetrical moieties. The South Women, along with the East and West Tomb principal personages and the rest of the East Tomb, enjoyed a healthier life than the North Trench individuals and North Women. In understanding the nature of the North Women, it is more significant that biologically they are quite distinct from all other groups in our sample. Together with the fact that they were consistently associated with Mochecoid artifacts, we suggest that they represent Moche descendants who were integrated into a multi-cultural society with Sicán political dominance and perhaps patrilocal rule. The emerging picture of the multi-cultural constitution of Middle Sicán society found independent support from materials analyses of ceramics from the West Tomb (see Shimada et al. 2004).

Above findings, along with ground-penetrating radar (GPR) survey data provide strong support for our hypothesis regarding relationships among elite shafttombs under and around the Huaca Loro pyramid and offer a new perspective on the function of Middle Sicán pyramidal structures (Shimada et al. 2004, 2005). The 1997 ground-penetrating radar survey and accompanying test excavations at Huaca Loro have further clarified the situation at hand. The latest radar prospection took advantage of deep erosional cuts in the pyramidal body made by the 1983 El Niño rains. As Shimada had inferred, it revealed the presence of what appears to be a solid adobe brick core structure at the center bottom of the pyramid and a deep shaft reaching perhaps some 10 m below the base of the pyramid. In addition, a test excavation at the northwest corner of the pyramid showed that the deep pit that we inferred to be an intact Middle Sicán shafttomb had its opening some 5 m below the surface under a thick layer of artificial foundation fill upon which the base of the pyramid was built. In 2005, with the collaboration of H. Watanabe, we conducted additional GPR survey of the west basal area of the Huaca Loro mound and found what appears to be an intact cemetery. The five-month 2006 season was dedicated to large-scale excavation of the inferred cemetery. Major findings of this excavation are found in the attached paper (downloadable PDF file) that was presented at the 2007 Annual Meeting of the Society for American Archaeology in Austin, Texas.

Overall, interdisciplinary investigation by the Sicán Archaeological Project has indicated that there is indeed a planned Middle Sicán cemetery below the Huaca Loro pyramidal body organized around a possible central shafttomb. Further, there are surrounding shafttombs below the outer edges of the pyramid and that the cemetery may extend to encompass both sides of the 150-m long platform. Clearly, the above implies that the pyramid was built later than the shafttombs to seal and protect them. It now appears that the pyramid served as a monumental tombstone for the deceased founding ancestor and members of a ruling lineage interred under and around it, as well as the altar for their continuing worship. The inferred existence of a masterplan that guided the preparation of shafttombs and the associated pyramidal construction argues for an ancestor worship cult, considerable social cohesion, political and economic power, and the enduring status of the elite. In general, the degree and scale of planning evident in the Huaca Loro cemetery and pyramid - and the social and economic implications of such planning - have not been considered previously in Peruvian archaeology with the exception of the Chimú “royal burial platforms.”

It should be remembered that Huaca Loro is not a unique situation. At the site of Sicán, there is another monumental pyramid, Huaca Santillo (or Soltillo), that has an identical architectural layout composed of a truncated pyramid with a long platform oriented north-south. A major shafttomb that was situated at the same relative location as the East Tomb was looted sometime in 1960s. Evidence that truncated pyramids or platform mounds were built over or closely accompanied by major elite tombs also exists for Huaca El Corte, Rodillona, and Las Ventanas. Overall, the site of Sicán with these constructions can be justifiably characterized as a unique ceremonial city.

Through systematic analysis of excavated tombs, we have been able to make a tentative characterization of the Middle Sicán social organization. Clearly differentiated access to metals serves to delineate four levels of social status (Shimada 1994b, 1995; Shimada et al. 2004). The lowest group was buried in an extended position in shallow, simple pits (< 2 m in any one dimension) without any metal objects. Burials of the next group ("commoners") were the most common, and differed from the first in having either extended or flexed position and arsenical bronze objects. The two highest groups ("lower" and "upper" elite) were typically buried in a seated position in square or rectangular pits at least 3 m in depth. The lower elite had access to arsenical bronze and tumbaga objects, while the upper elite distinguished itself by having had access to the full spectrum of metal products produced within Middle Sicán society, from mass-produced arsenical bronze items to the most exclusive, custom-made high karat gold.

Table 1: Differential Metal Access Model of Middle Sicán Social HierarchyThere are other features of tombs such as the distribution of different beads that yield a similar picture of Middle Sicán social hierarchy. Among those containing metal objects, iconographic content, stylistic refinement, and the material and technical qualities of metal artifacts also co-vary to form three distinct groups (Shimada et al. 2004). The distribution and nature of production of different ceramics provide further support of four-tier social stratification (Cleland and Shimada 1994, 1998). The lowest group had only utilitarian plain and paddled wares, the first through third groups had those and mold-made single spout bottles, and only the two elite groups had double-spout bottles covered by tumbaga sheets.

The above comparative study of tombs reveals other patterns that deserve future investigation, for example, burial position. Adults of either sex of the upper two classes are buried in seated, cross-legged or tightly flexed position, while those of the lowest class are extended. Commoner burials are found fully extended or seated, cross-legged. If burial position reflects widely shared ideology or long-standing tradition, the juxtaposition of two burial positions within a single social class with no apparent correlation with age, sex, or composition of funerary goods may well indicate the coexistence of two ethnic populations integrated within Middle Sicán society. If so, the seated or flexed position may be indicative of membership in the socially dominant ethnic group. Overall, the above lines of evidence produce a consistent picture of highly regimented access to certain kinds of material goods and a rigid social hierarchy in Middle Sicán society.

Another future research direction to emerge from the study of mortuary practices and goods is elucidation of the relationship between the Middle Sicán and contemporaneous Manteño culture of the south-central coast of Ecuador. Close contact between them is suggested not only by the aforementioned trade in Spondylus and Conus shells and distribution of inferred primitive currencies, but also by the presence of gold objects and pottery vessels bearing Manteño motifs (e.g., "Earth Monster") in the Huaca Loro East and West tombs. It is also intriguing to note that the woman in prone position noted above is in an essentially identical position to that of the "Earth Mother" in contemporary Manteño art. Future DNA studies of elite burials from these two cultures may even reveal a marriage alliance or immigration.

Similarly, possible religious and economic interaction between the Middle Sicán and Tiwanaku cultures remains to be examined. Lines of evidence pointing to such interaction include: (1) the central importance of a front-facing, standing deity holding a staff, a beaker, a scepter and/or spear-thrower; (2) production of arsenical copper; (3) importance of ritual beakers with outflaring rims and raised horizontal bands (keros); and (4) temporal coincidence (ca. A.D. 900-1100) of the expansive phases of both the Sicán (Middle phase) and Tiwanaku (Phases 4 and 5).

E. Conclusion

Through a sustained interdisciplinary investigation and regional approach, the SAP has defined various major features and achievements of the Sicán culture. Far from being an "epigonal" culture that followed the illustrious Wari and Tiwanaku cultures (Uhle 1903), the Middle Sicán culture was a highly distinctive, complex and influential culture with political and ideological hegemony over a 400-km stretch of the coast (Shimada 1995, 2000). Overall, the Middle Sicán was arguably the most powerful, influential, and materially rich culture in Peru for its time period. It was characterized by a distinctive religious art that fused selected aspects of the Mochica and Wari art into a new whole, advanced metallurgical and ceramic technologies, an extensive trade network and territory, elite shafttomb-monumental temple complexes (ancestor cult), and a theocratic state underwritten by a highly productive regional and interregional economy. The trade network was impressive not only in its physical extent (ca. 200 and 1500 km along the east-west and north-south axes, respectively), but also for the range of environmental zones traversed, resources exploited (not to mention quantities), and the rapidity with which it was accomplished (perhaps within 50 years). The establishment of their economic sphere and attendant spread of Sicán ideology as embodied in their ceramics and metal objects in the true sense of the term constitutes an archaeological “horizon.” The Middle Sicán left behind unmistakable legacies, including an arsenical copper technology that brought the bronze age to northern Peru.

(Please see "Reccommended Readings" for details of references cited in the text above).