Purpose and Method The purpose of this paper is to present archaeological data directed toward further comprehensive hthic use-wear analysis including experimental studies That is, to separate microwear which seems to be a result of use from other various microscopic phenomena on the surface of microblades. Firstly, under a binocular microscope with a magnification of 80 to 100, we observed the surface of more than one hundred microblades of certain technotypological features On each microblade, a 2×4 mm grid was employed to provide roughly equal units for comparison. Based on this grid, striations and microflaking scars found were classified according to their size (or length) and direction Secondly, to understand the nature of each wear pattern, its location and density on each microblade was examined, as well as the relationship between microblade form and appearance of these wear patterns Materials 126 obsidian microblades were observed and analysed These artifacts were recovered from the upper most loamy layer (late Pleistocene deposits) at Tama New Town site No 769, about 30 km to the west of the center of Tokyo These microblades were selected at random from about 300 microblades recovered from the same layer The microblades used in this analysis displayed material and size characteristics generally observed for similar hthics found elsewhere in this region Results and Interpretations As a result of the observations and analysis, following points were noted Besides microflakings, three types of striations and a "frosted glass"-like wear were found The three types of striations are as follows, Type I Long striations extending over more than one 2×4 mm observation grid and paralleling the lateral edge of microblades Type II This type of striation is long, also exceeding grid dimensions and is oblique or perpendicular to the lateral edges. Type III This type of striation is very short, lying within the grid and random in direction Striations of Type III and the "frosted glass"-like wear existed on almost every microblade As these wear patterns exist equally on every part of the microblades in high frequency, it is very likely that they were formed by accidental factors The two other types of striation, Type I and Type II, and microflakings are assumed to have some relationship to the use of microblades, judging from location, and the shape, length of microblades displaying these vear patterns Among these, it is thought that striations of Type I were most likely a result of microblade use This is because, firstly, most striations of Type I are located near to the lateral edges of micioblades, parallel to the edges, and appear in high density Secondly, the location of Type II striations and microflakmgs show distinctive characteristics when accompanied by Type I, while random in nature when not accompanied by Type I And more over, most microblades with striations of Type I have strait lateral edges parallel to each other, and the lateral view of these microblades are less curved because in many cases, their bulb and distal ends have been removed These facts are very interesting when the haftmg of microblades to wood or bone handle is considered. The results of this analysis were promising and it is hoped that these results; will contribute to a new direction in functional analysis of microblades in Japan, as well as stimulate further use-wear analysis.
|
