Mineral composition and rock provenance of a prehistoric stone axe head from the surroundings of Nevestino village, Kyustendil District, SW Bulgaria

摘要

This paper presents a petrographical study of a stone axe head which is an exhibit of the Historical Museum in the town of Kyustendil, SW Bulgaria, and is of supposed Bronze Age origin. The methods used comprise optical and electron microscopy, and electron microprobe analysis. The results show that the stone axe head is made of microgabbro rock. This rock in mineral composition, mineral chemistry, and metamorphic alteration is similar to gabbro rocks of the Struma Diorite Formation, which crops out on large areas in SW Bulgaria. Thus, it is proposed that the rock provenance of the studied stone tool is the Vlahina Planina mountain or Osogovo Planina one since the nearest outcrops of the Struma Diorite Formation there are in a distance of 4-5km away from the place of finding. Use of local rock for production of an every-day tool reveals good knowledge of local natural materials by prehistoric people and suggests a settled way of life.