During the 2003 field season the Upper Colca team did not have digital proveniencing of sufficient accuracy (sub-centimeter accuracy) to permit digital records from excavation and therefore the team returned to using more traditional methods. Collections were bagged and tagged using the unit/level/feature spatial proveniencing that facilitates locating the units without referencing a computer database or a locus sheet. Arbitrary spatial units included levels (15 cm or smaller natural levels), 1x1m units, and 50cm quads with letters in reading orientation following a convention borrowed from Mark Aldenderfer's excavation methods.

Figure 5-8. (a) Example of proveniencing for four 50cm quads within a 1x1m unit with an item in quad d, north is at the top of the page. (b) An example of a paper tag showing site name, unit/level and quad/feature number, artifact type, date, and excavator initials.

The advantage to these explicit field proveniences is that bags and artifacts being returned from screening can easily be relocated to their origin provenience in the field (in the excavation block) based on the unit coordinate system. The disadvantage is that these provenience values, such as U2 / 4d / F2 do not code easily into a database and while some method of geocoding of these addresses is conceivable, the technical advantage to doing so is slim. In such cases, the European locus system, or a lot number system based on integer key fields, is much more effective and computer-ready.

The Upper Colca project ended up using a system that resembles, in some ways, the postal service system: street addresses are akin to the unit/level/feature codes in the sense that they are field-useable (one can find a house without referencing a database). Street addresses are supplemented by a Zip code in the US, which in the form of a nine digit zip, is house specific. This small amount of redundancy minimizes error in the postal service, and in the Upper Colca proveniencing a similar system worked for minimizing error in collections from excavation.

Field proveniencing was supplemented by Lot numbers during the first phase of analysis and data entry in the laboratory. Consistent with the Arch ID - RotuloID strategy, each spatial provenience was given an integer LotID number, and then artifacts within each spatial provenience received a RotuloID number in a sequence ( Rotulois Spanish for index number). Thus, for surface materials collected in 2003 a A03- [ArchID].[RotuloID]code specifies spatial location and then item identity, whereas for materials from excavation in 2003 the L03- [LotID].[RotuloID]code specifies excavation provenience (Lot) and artifact identity. As mentioned, the LotID number system was redundant with the unit/level/feature proveniencing system written on tags, but in reality it referred directly to the database unique ID # which is unavoidable in database organization. This redundancy was actually useful in a few circumstances and it serves to minimize error, as the digital ID# system appeared on the artifact ID# tags, and vice versa. Ultimately the Lot# system became the one that is referenced in queries after lab work was complete; it is the most up-to-date system in the database.