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Specimen FS 105 is a medium-sized tri -notched or Mallory point. This type occurred in <br />three sites (5MF454, 5MF3187, and 5MF3472) in Northwest Colorado (Metcalf 2011:75). At <br />5MF454 and 5MF3472, this type was found in association with the McKean Lanceolate; and, <br />at 5MF3187, it was found with the Duncan type as well. All have a McKean Complex <br />association and are assigned to the Middle Archaic with a general age range of 5000 to 3000 BP <br />(Frison 1991:91). The McKean Lanceolate and Mallory points generally are in deposits that <br />have earlier Middle Archaic dates — pre -3500 BP (Kornfeld et al. 1995:269). <br />10.2 Lithic Tool Stone Materials <br />A one-third sample (approximately 800 flakes) were examined for material types. That <br />sample consisted almost entirely of chert, and at least half of the flakes are 15mm in size or <br />smaller. The majority of larger flakes do not exceed 35mm in size and exhibit at least some <br />degree of cortex. Approximately 20% of the overall assemblage has cortex and 10% has <br />evidence of heat treatment in the form of potlidding or crazing. Quartzite was limited to less <br />than 5% of the entire assemblage. Many of the quartzite flakes were of poor toolstone quality <br />and were likely procured from local stream deposits. A few specimens may be from the <br />Dakota (Cretaceous) Formation. <br />The main source of chert material appears to be cobbles and pebbles procured from a <br />local stream or river. Additionally, a variegated chert from the Burro Canyon Formation <br />(Cretaceous) is present in notable quantities. This chert is distinguished by the presence of <br />light gray to white chalcedony inclusions and occurs as layers interbedded with shale and <br />sandstone. It is most commonly translucent dark gray and black; however, it also occurs as <br />light brown, opaque tan, and opaque, mottled light gray and black. <br />Bridger Formation (Eocene) chert or "Tiger Chert" is a notable lithic material found on <br />the site. This material, found in southern Wyoming and in northern Colorado, forms in bedded <br />limestones of the Bridger Formation. The distinct banding is a result of the preservation of <br />stromatolitic structures and is apparent on weathered specimens (Loosle 2000; Love 1977). <br />Kremmling chert is present throughout the assemblage. Outcrops of Kremmling chert are <br />located in Middle Park, Colorado. Several flakes of red jasper were recovered and are small - <br />to -micro in size. Chalcedony is also present in small quantities and occurs throughout vast <br />locations in Colorado (Eckles 1997). One obsidian microflake was collected. <br />The terminology used here has its basis in the geologic literature and is fully elucidated <br />in Miller (1992), however, other descriptive names are applied to these rocks. For instance, <br />translucent opalitic chert is commonly called chalcedony. Chalcedony is a crypto -crystalline <br />29 <br />