We are now progressing down through the next layer of light yellow-brown sand which also contains a lot of obsidian flakes. There is a lot of discussion about how this mixed sand and flake layer could be explained. At about 30 cm down into the layer we started finding bones of seal, and teeth of white pointer shark.
A surprising choice of tool
Progress has slowed considerably as we try to excavate and lift the bone without breaking it. So far it is all on the same level, possibly a butchery area with associated large obsidian flakes used to cut up the flesh.
This is an exciting find as it is not often such intact sites are discovered. Surprisingly the occupants were flaking mainly obsidian, with very little basalt and chert, even though chert is present on the island.
The assemblage of flakes will make a great research topic on the technology of stone flaking, and also which sources of obsidian have been used.
Lifting fragile bone
Conservator Dilys Johns from the Anthropology Department at the University of Auckland has arrived to help us lift some of the fragile bone. The bone has to carefully have the sand moved away from around it leaving a pedestal of sand with the bone on it. Although careful work is required, the excavator also has to work fast as the bone dries out quickly in the air.
Once the bone it is fully exposed it is carefully removed and placed in a box. In the lab it will be exposed and dried under controlled conditions. Some of the bone is so degraded it will fragment as soon as it is lifted so it is photographed and the location shot in with the total station but not removed as a sample.
Intact bones can be consolidated before being lifted to ensure they hold together. We can examine the bones for cut marks to work out how the animals were butchered, and the bones can be identified to body part and then to genus and species, and sometimes age within broad brackets.
Post by: Louise Furey
Dr Louise Furey is the E. E. Vaile Curator of Archaeology at Auckland Museum. Louise has been an archaeologist for 35 years and has carried out site assessments and archaeological excavations in the upper North Island. She holds an MA (Hons) and a Doctorate of Science degree from the University of Auckland.
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