2010-12-17_REVISION - C1981019 (114)

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Historic Properties Treatinent Plan, Collom Mine, Colorado 36 they are typically thick and blocky in cross section and e irregular in outline. Flake scars are large g and irregularly placed. The preblank category may in some cases include bifacial cores, but in most cases the two functions cannot be distinguished and in fact may have coincided. Blanks comprise specimens at the next general stage of bifacial reduction. These artifacts are characterized by further reduction from the preblank stage, resulting in roughly regularized outlines and cross sections. They are more thoroughly flaked than preblanks, generally obscuring most of the form of the original pieces of material from which they were manufactured, and they have thinner cross sections. The flake scars tend to be smaller and more carefully placed and controlled than on preblanks, although they are less regularized and less finely flaked than preforms, and the flake scars are often still relatively large. They generally reflect only percussion flaking. Preforms are artifacts at the next stage in the reduction sequence. They have regular outlines and regular thin cross sections; they have been finely and thoroughly flaked and generally retain minimal cortex, if any. They are distinguished from final bifaces by the absence of fine edge retouch and /or hafting modifications characteristic of bifaces that have been completely reduced to an ideal end - product. In general, most artifacts falling into the preform category represent discarded or broken manufacture stages originally destined for completion as final bifaces. Finally, the last stage of the reduction sequence includes formalized (usually hafted) biface tools and fully thinned bifaces that exhibit fine edge modification are classified as final bifaces. These artifacts are distinguished from preforms and thin blanks by the fact that they have modifications for hafting and /or fine, marginal pressure retouch and /or are distinctively shaped biface types not typically further reduced into other forms. The final biface category includes projectile points, other hafted bifaces, drills, and bifaces with highly formalized edges produced by pressure flaking. It also includes other specialized biface tool forms and undiagnostic biface fragments from finished formalized bifaces (e.g., projectile point tips). For hafted final bifaces, additional attributes including neck width, base width, and stem length are measured. 47599 TRC Mariah Associates Inc.