Tsodilo (Botswana) : Hunt for origins of beautiful Tsodilo ritual stones begins

Hunt for origins of beautiful Tsodilo ritual stones begins

Monkagedi Gaotlhobogwe

Source - http://www.mmegi.bw/index.php?sid=7&aid=750&dir=2011/August/Friday5 

Researchers in geology and archaeology fields have started a P500 000-project to find answers to the origins of the beautiful silcrete stones at an archaeological site at the very, very top of the Tsodilo Hill.

The rare finds that startled researchers include chalcedony, silcrete and an as yet to be identified shiny, white, silcretised organic material.  Researchers are convinced that Tsodilo, whose rocks or stones are mainly quartz, cannot be the source of the semi-precious stones found at a cave they excavated.

 However, they say the silcrete is available within 40-150km from Tsodilo.  That is the area they will be traversing to compare materials using the technology called finger-printing.

Archaeologist, Professor Sheila Coulson of the University of Oslo, whose excavations at the Tsodilo Hill caves, amongst others, revealed the stone tools, has concluded the stones were imported to the site as they are not locally available, but the one question that remains unanswered is: Where could the users of the tools have collected these materials that they brought to the cave for rituals?

According to the researcher, definitive evidence of the transport of raw materials to Tsodilo Hills would indicate the earliest known recognition of the properties of stone sources anywhere in the world, and may imply the existence of ancient exchange systems, trade alliances or symbolic behaviour.

The researchers will be using a method called fingerprinting technique, to search for the answers. Archaeologists say if the fingerprinting technique is successful, it has the potential to revolutionise our understanding of the origins of human behavioural traits.  Recent genetic research indicates that the earliest modern humans migrated from southern Africa during the middle Stone Age. 

The archaeological record from well-dated middle Stone Age sites like White Paintings Shelter (at Tsodilo Hills) should, therefore, contain vital clues to the development of the cognitive abilities that define modern human behaviour.

Now Coulson, Prof David Nash, and Dr Stewart Ullyott will next week be in the Tsodilo area, traversing some 150km of water sources where similar rocks exist, as part of a pioneering research project, which aims to identify the sources of materials used in the manufacture of tools excavated from the middle stone age archaeological site, believed to be over 70 000 years old.

CIV  105 :   Civilisations Africaines

According to a brief from the University of Brighton, England, which sponsors the research, researchers Nash and Ullyott will be working alongside colleagues from the University of Oslo, the University of Botswana (UB) and the Botswana National Museum on the project.

The goal of the project is to pilot a geochemical fingerprinting technique to establish the provenance of stone used in tool-making at white Paintings Shelter in the Tsodilo Hills, Botswana's only UNESCO World Heritage Site.

 According to research findings a majority of the tools at the site are made from silcrete, a highly resistant silica-cemented duricrust with similar properties to flint. 

However, no silcrete outcrops exist within the immediate vicinity of the Tsodilo Hills, with previous studies suggesting that the tools were made using silcrete sourced from 40 - 100km away. 

Until now, it has proved impossible to identify specific stone sources, as the necessary analytical approaches do not exist.
Coulson says the three-week field research programme will involve the sampling of all potential raw material sites within 150km of the Tsodilo Hills.  Archaeological surveys will be carried out at each silcrete outcrop to identify the presence of any diagnostic middle stone age manufacturing debris, which would indicate that the sites were used as quarries.

Work will also take place at the Botswana National Museum where collections of silcrete tools and associated waste debris from White Paintings Shelter are archived.  Waste flakes from these collections, including materials from different occupation levels, will be sampled, she explained.

Samples of silcrete raw materials and archaeological waste flakes will be returned to Brighton and analysed by Nash, Ullyott and colleague Dr Laurence Hopkinson, to identify their distinctive geochemical, mineralogical and petrological signatures, with statistical techniques used to match each waste flake to its potential source.  The distribution of sources will be mapped to identify changing patterns in the location of resources used for tool-making over time.