Once an archeologist can control for the geochemical signature of the obsidian (e.g., the "source") and temperature (usually approximated using an "effective hydration temperature" or EHT coefficient), he or she may be able to date the artifact using the obsidian hydration technique.
Water vapor pressure may also affect the rate of obsidian hydration.
- Variation in Inca building stone quarry operations in Ecuador and Peru.
- Clay and temper mining practices in the Lake Titicaca Basin.
Indeed, communal rituals and performance were apparently limited to the pilgrimage center of Cahuachi and associated features of the built environment such as the Nasca geoglyphs.
- The Huarhua rock salt mine: possible archaeological implications of modern salt extraction practices.
Obsidian obeys the property of mineral hydration, and absorbs water when exposed to air.
When an unworked nodule of obsidian is initially fractured, there is typically less than 1% water present.
Mining and Quarrying in the Ancient Andes focuses on the primary extraction of a variety of materials that, in many cases, were used by cultures like the Inca, Wari and Tiwanaku in well-studied sites.
The book delves into the broader mining practices that link diverse materials for a fascinating tour of the social and economic life of the prehispanic period, and of ancient technologies, some of which are still in use.
The use of Secondary ion mass spectrometry (SIMS) in the measurement of obsidian hydration dating was introduced by two independent research teams in 2002. It has also been applied in South America, the Middle East, the Pacific Islands, including New Zealand and Mediterranean Basin.