Polish is quantitatively different on quartzite flakes used on different worked materials

PLoS One. 2020 Dec 3;15(12):e0243295. doi: 10.1371/journal.pone.0243295. eCollection 2020.

Abstract

Metrology has been successfully used in the last decade to quantify use-wear on stone tools. Such techniques have been mostly applied to fine-grained rocks (chert), while studies on coarse-grained raw materials have been relatively infrequent. In this study, confocal microscopy was employed to investigate polished surfaces on a coarse-grained lithology, quartzite. Wear originating from contact with five different worked materials were classified in a data-driven approach using machine learning. Two different classifiers, a decision tree and a support-vector machine, were used to assign the different textures to a worked material based on a selected number of parameters (Mean density of furrows, Mean depth of furrows, Core material volume-Vmc). The method proved successful, presenting high scores for bone and hide (100%). The obtained classification rates are satisfactory for the other worked materials, with the only exception of cane, which shows overlaps with other materials. Although the results presented here are preliminary, they can be used to develop future studies on quartzite including enlarged sample sizes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Quartz / chemistry*
  • Quartz / classification*

Substances

  • Quartz

Grants and funding

This research has been supported within the Römisch-Germanisches Zentralmuseum – Leibniz Research Institute for Archaeology by German Federal and Rhineland Palatinate funding (Sondertatbestand “Spurenlabor”), the Spanish MICINU-FEDER project PGC2018-093925-B-C32, the Catalan AGAUR project 2017-SGR-1040, the URV project 2019-PFR-URV-91 and the Fragmented Heritage Project (AH/L00688X/1).