In the introduction of the book I pulled out one quote explaining that for prehistoric people there was not a strict division of tool style with function or the same job done with several different tools. Although the style vs function argument is not one I plan on discussing much in my methodological approach to archaeological use-wear it does bring up the fact that tools were used for multiple uses so some tools may have many identifiers for what they were used for. On the other hand the original purpose of a tool may have adapted or changed into something else, completely erasing all of the original traces of work on a stone tool. I find this less likely as I have seen examples of adaptive tool change (projectile to blade and vice versa) where the original traces are wiped out completely. As this is the founding work on use-wear for intensive purposes, this was not as obvious. Semenov does cover that use-wear is not an end all be all in terms of stone tools but the traces left behind on stone tools does provide a range of variety of use. It is best used in conjunction with precise evidence found in relation to accurate superposition during excavation.
Semenov provided a quote from N.P. Tikhonov, which is probably the earliest acknowledgement of the usefulness of traces on stone tools: "This comprises study of the technique of manufacture beginning with the extraction of the material and going right up to the final division into different shapes and forms. It is necessary to study with the microscope and spectroscope the appearance of the surface, to discover the traces of instruments and means of boring, grinding, etc. and so by analogies with contemporary traditional methods in the same regions re-create the technical environment in which work took place."
Identifying marks on such a hard material like flint, that could be seen with the naked eye insinuated that there could be microscope marks that could not be seen. This is what led Semenov to use microscopy with binocular lens magnification with a max of 45X on ancient stone tools.
Semenov's original usage of the word polish (or rubbing) was specifically a type of wear as opposed to accumulation of a type of sheen. Through polish Semenov identified many flakes (simply waste products at the time) as tools.
Semenov's bread and butter is the striation. Striations are the most important factor in terms of a tools use.
Patination of stone tools, especially really ancient ones like Paleo, may wear down through time from wind and water, hence changing color and removing many of the original wear traces.
Striations can be confused with manufacture marks that look like stepped or rib-like lines. They vary but are very large on some tools and have nothing in common with work. Work through time alters the shape of the tool and what striations can be viewed through time. The abrasive agents leaving traces on stone tools may abrade themselves as the entire morphology of the tool changes completely. This is especially true of retouch which will completely remove traces. This is also true with the quality of the material as its wearability can depend on the shape and working part with the time used in work.
Three degrees of wear on a tool from friction with another object:
1. Polishing (small specific pressure with dispersion of minute particles)
2. Grinding (high pressure with dispersion of many particles)
3. Rasping (large specific pressure with macroscopic destruction of the surface)
Friction never happens with clean surfaces. There are always small particles of dust that get between the tool and its surface that create abrasions such as fat and sweat excretions from the hand or quartz grains.
All aspects of wear can be reduced to a twofold change:
1. The tool is altered in shape and reduced in volume.
2. The non-working part suffers very slight wear except in those parts which were gripped with the hand or handle which cause friction.
Polishing is the most noticeable before all other marks on a stones surface. No matter the hardness, traces of rubbing against the skin from the users grip were usually left on the tool.
Grinding, polish, and striations can also happen from surface attrition. When tools used on bone, wood and skin are used a magnifying aid is necessary to view the striations in the majority of cases.
Cherts show striations emerge much less clearly *IMPORTANT*
Striations arise when these actions are performed: cutting, whittling, sawing, chopping, boring, drilling, piercing, grooving, and grinding. When the tool does not penetrate into the thickness of an object show chip-marks, holes, roughening, and dents.
The destruction or trace marks on the tool all depend upon the angle of inclination and the force applied.
Piercing:
normally not done by straight pressure
accompanied by turns of hand to right and left in quarter or half circle
wear influenced by two movements: straight and rotary
traces reflect both movements
projections show polishing on the side of point & edge of depressions on side of butt end
Drilling:
piercing with quarter circle rotation
Types of drilling:
one handed removing hand each time
one handed continuous without removing hand and pivoting alternating direction
two handed continuous drilling one direction
two handed continuous alternating rotation
Tool always leans to an axis of rotation leaving a bigger hole than side of the drill (Mostly initial start of drilling as sharp turns will break the drill). The harder the material the less deviation will occur.
Stone on stone very clear striations
Shell and Bone less clear. Working end vague gloss seen
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