Some of these are simple rituals carried out by individuals or families for luck in travel and trade or for the protection of crops and herds.

More-complex rites involve a specialist who is paid according to the complexity and length of the ceremonial.

The thermoluminescence technique has the added benefit of directly dating pottery sherds, which can be useful for developing ceramic cross-dating sequences.

ABSTRACT: With improvements in methodology and instrumentation, luminescence dating is becoming a much more useful chronometric tool in archaeology.

It was during this turbulent period and Diego de Vargas 1692 Re-Conquest that Pueblo Indians escaping retaliation for the rebellion lived among the Navajos and introduced both sheep and weaving technology to the Navajo to a degree such that written records among certain Spanish documentation , covering a period from 1706-1743, records the Navajo keeping sheep and weaving wool blankets during that period.

Pueblo manta, late 19th century The earliest known surviving examples of Navajo blankets are but fragments dating from the 1805 Massacre Cave site near Chinle, Arizona and Canyon de Chelly.

Navajo men and women also continued the tradition of volunteering for the armed services at a high rate, perhaps as an expression of a cultural ethic that emphasizes both personal competence and community.

In maintaining these disparate traditions, the Navajo have been cultural innovators.

The Pueblo tribes grew cotton and wove blankets and garments on a distinctive pueblo loom hundreds of years before the Spanish arrived (these weaving skills perhaps brought up by Indians from what is now Mexico and Central America), yet it was the Spanish who first introduced sheep to the Southwest.

The earliest sheep brought to the Southwest by the Spanish was the churro, a small sheep with very long silky, smooth stapled wool perfect for weaving and in a variety of natural shades: dark brown, tan and cream.

The region is mainly arid, however, and generally will not support enough agriculture and livestock to provide a livelihood for all of its residents.