The multiple reciprocal exchanges model involves the direct acquisition of obsidian by local people for the express purpose of transferring the obsidian to neighboring communities in exchange for other items. In this model, people residing in Chivay area, perhaps no more than one day's travel from the source, procure material and transport it to a location where the obsidian is then exchanged with neighbors.
This kind of procurement resembles Renfrew's (1975: 520) "Reciprocity" and the "Down-the-line" modes (see Figure 2-2), where goods are exchanged with neighboring groups of roughly equal status through a variety of configurations that are essentially reciprocal in some form. While a synchronic barter of obsidian for, say, a chunk of ochre from the neighboring region is easiest to describe conceptually, reciprocity relationships are a manifestation of a wide range of social mechanisms (Section 2.2.2). In the context of the Chivay area, reciprocal exchange arrangements such as barter for other products, or for grazing rights, for labor, or for social functions such as bridewealth, may be evident. Furthermore, delayed reciprocal arrangements between neighbors are extremely common. Evidence of Down-the-line exchange may be encountered in a wide variety of socio-political contexts from Archaic Foragers to agro-pastoralists living on the periphery of states during the Late Prehispanic. If demand for a product is sufficiently high, archaeological evidence may be encountered of individuals devoting themselves to procurement in order to satisfy regional demand, but substantial quantities of goods would have to be reciprocated because the households that are sponsoring this increased procurement would have fewer provisioners working to bring subsistence to the household. Thus, if down-the-line demand is sufficiently great then the households devoting themselves to elevated rates of procurement would need to barter products for subsistence goods. In the Andes, the pattern observed from items like salt (Concha Contreras 1975: 74-76;Nielsen 2000) suggests that in modern circumstances when demand, and barter values, are sufficiently high, then the down-the-line network may be simply by-passed in favor of procurement through personal or caravan acquisition. Caravans from the consuming zone or adjacent highland areas will make the journey to procure the material and transport it for household use and for barter (a combination of the Direct Access model and the Independent Caravans model).
In a functioning Down-the-line system the flow of information is also important. The changes in the regional demand for a product like obsidian can return to the source area procurers through direct requests, or it might be reflected in increased barter value in a market context. Information exchange may also return specific demands from consumers as to the size, form, or quality of the source material. The temporal regularity of down-the-line reciprocal trade may also be quite variable, as down-the-line networks may dwindle and then be revived during a seasonal gathering or ceremonial occasion. Reciprocal relationships can take the form of mutualism and buffering, they may result from a need to complement the resources on a neighbor's territory, and they often present opportunities for ambitious individuals to advance their interests through differential access to non-local goods.
Down-the-line procurement involves local people visiting the Chivay source and acquiring goods to supply the reciprocal exchange network, however large that it may be. In the quarry area one should expect local visitors, and therefore local styles in both discarded materials and local architecture. Procurement may take place in the context of embedded economic activities, such as hunting forays into the high country or pasturing of camelids in the rich bofedal adjacent to the source.
If reciprocation for obsidian takes the form of portable objects, such as non-local ceramics, one may encounter diagnostic, non-local goods in the communities adjacent to the obsidian source. These may be in the form of styles belonging to neighboring communities, or more exotic styles may be found on non-local goods that could have arrived through the exchange network from even more distant areas. There is a high likelihood that reciprocation for obsidian would have taken place in other forms as well: goods that are perishable, labor, or other assets that are otherwise less easy to detect.
If locals are involved obsidian procurement at the Chivay source one may also find that the large nodules available at the Chivay source are used in the local economy as well. That is, if nodules in the Chivay source are up to 30cm in length then large flakes, either cortical or non-cortical, may be expected to have been discarded in residential contexts in local communities. If large nodules are available then those that are not exchanged with reciprocal partners are put to use for local needs. Thus when large cores and flakes are procured in the Chivay source area, then appropriately large flakes should be discarded in the middens of communities in the adjacent consumption zone in the upper Colca.
Procurement and initial reduction at the source will have relatively low variability because it is conducted by the same local methods. Local people will have better knowledge of high quality extraction loci and perhaps there is lower variability in procurement locations as a result. As reciprocity networks, and particularly barter arrangements, are contingent on visual attributes of bartered items one should expect medium reduction of material at the source or in the adjacent communities. At the very least, nodules will be partially decorticated and an initial strike that provides entry into the core should be expected, as this serves to expose the quality of material on the interior to barter partners. Furthermore, if transport does not involve camelid cargo animals (because reciprocity is either taking place pre-domestication during the Archaic Forager period, or otherwise does not involve camelids) one might expect a greater concern for the weight of the nodules and therefore further reduction in the vicinity of the obsidian source.
More advanced reduction may also be expected as it minimizes risk and waste by producing blanks, preforms, and prepared cores in the vicinity of the source where obsidian is abundant. However, according to the Down-the-line model producers have the greatest social distance, and therefore the least information, about their consumers. Advanced reduction limits the possible forms that artifacts may take, and therefore producers would need to know what kinds of tools consumers were planning to produce in order to move beyond initial stages of reduction. Thus medium level reduction might be expected, but not an abundance of advanced reduction at the Chivay obsidian source.