EMAP Obsidian Flake Database

The Eastern Mimbres Archaeological Project (EMAP), co-directed by Drs. Margaret Nelson and Michelle Hegmon began in 1990, building upon earlier work by Nelson. EMAP focuses on the later (post-AD 1000) prehistory of the eastern Mimbres area, a portion of the Mimbres region in southwest New Mexico. In 1982 Nelson was at the University of New Mexico, Albuquerque and in the early 1990s at the State University of New York, Buffalo, and Hegmon was at New Mexico State University, Las Cruces. In 1995 both moved to Arizona State University, where they and the project reside today. Earlier work by EMAP focused on the post-AD 1150 period, specifically what is now called the Reorganization phase [1150-early 1200s] of the Postclassic period. After 1998 the project focused on the Classic period (AD 1000-1130). Key research issues include the social and ecological dynamics of reorganization, residential mobility among farmers, environmental impact and sustainable farming practices, pottery production and exchange, and community organization. 133 samples have been tested. See the Obsidian Hydration Results for further information.

The full set of obsidian recovered by EMAP can be found by examining both the “Obsidian Flake Database” and the “Obsidian Inventory.”

The “Obsidian Flake Database” was created early in the project when each flake was inventoried individually. In 1989 the “Obsidian Inventory” was introduced in which groups of obsidian artifacts are recorded by provenience. Most flakes were recorded in that group data base, but a sample continued to be recorded individually through 2001. Thus the “Obsidian Flake Database” combined with the “Obsidian Inventory” offers the full obsidian dataset.

The two files have some duplication for the following proveniences:

- LA 37767 Unit 35

- LA 130191 Unit 21

- LA 70258 Units 1, 2, 3, 11, and 12

- LA 70259 Units 1, 2, 3, 4, 11, 12, and 13

For these units, samples of flakes from excavation are in the “Obsidian Flake Database.” The “Obsidian Inventory” is a complete count of flakes, cores, tools, and nodules from those proveniences.

A third data file, “Sourcing and Dating Obsidian” includes sample proveniences from which pieces were selected for sourcing and/or dating analysis. These are all listed in the “Obsidian Flake Database,” as well.