1 Chapter 1 FURTHER STUDIES OF ANCIENT BLACK GLASS: OBSIDIAN TRACING AND HYDRATION DATING TULARE LAKE WIDESTEM POINTS Jerry N. Hopkins, Alan P. Garfinkel, Alexander K. Rogers, Tim R. Carpenter and Craig E. Skinner Abstract: Widestem points are to some degree common at the Witt Site (Ca-Kin-32) locality of Tulare Lake. Within the Hopkins collection, there are 101 examples of widestem points that were complete enough to allow classification. These artifacts were manufactured from a variety of toolstone materials. Most of these points were fashioned from locally available chert (cryptocrystalline silicate = ccs) and other materials (fine grained volcanics = fgv) including basalt, fine grained igneous (aka rhyolite), quartz (crystal, milk white and rose) and quartzite (n = 65) along with (n = 36) specimens made of obsidian (obs). Virtually identical point forms to the Tulare Lake Widestems are recognized from Northern California and are identified at the Borax Lake Site (CA-LAK-36) and in the larger vicinity of the Clear Lake region. Those North Coast Range projectile point forms (known as Borax Lake Widestem Points) appear to overlap in age with both fluted points and crescents, but continue to be employed until a more recent era discontinuing at a time estimated to be 6,000 years cal b.p. In the present study, we formally classify Tulare Lake Widestem Point forms from Tulare Lake found within the Witt locality and determine whether they are of comparable age to other early Holocene artifacts recovered from Borax Lake. The entire sample of formally classifiable Tulare Lake Widestem Points manufactured from obsidian was analyzed to both chemically characterize these artifacts as to provenience (geographic source) and to determine their obsidian hydration measurements. Obsidian studies appear to date the Tulare Lake Widestem Points to an average age of 8,250 calibrated years before present. Applying a single standard deviation added to that mean or average provides a time range for the bulk of the Tulare Lake Widestem assemblage from ca. 7,500 to 9,000 years ago. Source determinations for Tulare Lake Widestem show that imported obsidian was coming from Fish Springs, Coso, Annadel and Casa Diablo obsidian sources. Most of the obsidian Widestems at Tulare Lake came from the Casa Diablo suite of obsidian sources. This obsidian toolstone contributes a significant portion to the Widestem assemblage and testifies to long range movement and the value of the imported toolstone to the indigenous people who occupied Tulare Lake. INTRODUCTION Proveniences for Tulare Lake Widestem Points Jerry Hopkins was the first to identify and describe the Tulare Lake Widestem Points, all of which were found in surficial contexts recovered mostly within boundaries of the Witt Site locality. These points have not previously been formally defined as a specific type of projectile point for the Tulare Lake region. Loci numbers (1 - 15) of the Witt locality were assigned by Hopkins to identify specific sub-locality collection zones where Paleoindian artifacts were found on Tulare Lake’s fossil shorelines (Township 23 South, Range 20 East) at elevations between 190 and 195 feet amsl (above mean sea level), a contour interval that marks the level at which Lake Tulare stood during late Pleistocene/early Holocene times. These eroded shorelines were