Heated-weaponry, a pilot study on trace formation on heat-treated silcrete

[en] The Middle Stone Age (MSA) in South Africa features technological innovations such as the intentional heat treatment of silcrete to enhance its knapping properties. Although the importance of heat-treated silcrete in MSA toolkits is acknowledged, there is a notable lack of understanding regarding how use-wear forms and appears on this diverse raw material. This gap results in a shortage of reference data for the functional analysis of archaeological finds, which often depend on models based on uniform materials such as flint. This experimental study examines macro- and micro-use-wear on heat-treated silcrete used in various activities, including projectile work. Findings show that macroscopic wear patterns—such as types of edge fractures—correlate with the hardness of the worked material and the motion involved, generally following the principles known from flint. However, the internal structure of silcrete, consisting of quartz grains embedded in a softer silica matrix, introduces distinctive modifications. Its heterogeneity makes interpreting individual fractures more complex, as their development is influenced by the internal grains. The study concludes that although broad principles of use-wear still apply, heat-treated silcrete displays a unique signature driven by its composite nature. Therefore, analysts should adopt a specialised interpretative approach that goes beyond simple analogies with flint. This research is a crucial step towards creating a comprehensive reference collection for more accurate identification of tool functions on this raw material.

Disciplines :

Archaeology

Author, co-author :

Oberholzer, Ronè ; Université de Liège - ULiège > Unités de recherche interfacultaires > Art, Archéologie et Patrimoine (AAP) ; Université de Liège - ULiège > Département des sciences historiques > TraceoLab

Rots, Veerle ; Université de Liège - ULiège > Unités de recherche interfacultaires > Art, Archéologie et Patrimoine (AAP) ; Université de Liège - ULiège > Département des sciences historiques > TraceoLab ; F.R.S.-FNRS, Belgium

Language :

English

Title :

Heated-weaponry, a pilot study on trace formation on heat-treated silcrete

Publication date :

September 2026

Journal title :

Journal of Archaeological Science: Reports

ISSN :

2352-409X

Publisher :

Elsevier Ltd

Volume :

Pages :

105801

Peer reviewed :

Peer Reviewed verified by ORBi

Additional URL :

https://api.elsevier.com/content/article/PII:S2352409X26002361?httpAccept=text/xml

Name of the research project :

GLUE

Funders :

FRS-FNRS
ULiège. ARC - Université de Liège. Actions de Recherche Concertées

Funding text :

The University of Liège generously provided funding for this research through the ARC (Concerted Research Actions) grant "GLUE". V. Rots is also indebted to the Fund for Scientific Research (F.R.S.-FNRS; DR).

Available on ORBi :

since 27 June 2026

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