The archaeologists here at Wairau Bar continue to amaze me with their cleverness. It really is impressive how they see things on a completely different level, and can deduce all kinds of information from the areas they are excavating, first with the naked eye, and later once they have analyzed all the data collected from each area. The ongoing digging of Area 1 provides a good example of this. If you’ve been reading the earlier posts, you may recall this pit is designated as a repatriation site, and when excavation began (it seems like a long time ago now) it appeared to have very little archaeological material in it – which was kind of the idea in the first place. At first it seemed like there may just be the remains of a few old fires, but over the last week, as they have painstakingly peeled away each layer, a whole other picture has emerged.
Although a lot of modern archaeology relies on technology and advanced electronics, such has the robotic theodolite and fluxgate magnetometer that I discussed in earlier posts, there’s still no substitute for the trained eye and experience of an expert. No sooner had we freed the adze from where it had lain for seven centuries, then the archaeologists were able to tell me all kinds of details about it, just from looking. For a start, even the location it was buried was significant. It had been deliberately placed at the bottom of a post hole from some kind of structure, probably as some kind of spiritual symbol.
Now to you or I, one rock may look pretty similar to another, but not only could Richard Walter tell me what kind of rock the adze was made of , he could even identity which particular hill it was quarried from! You can’t make a high impact tool like an adze out of just any kind of rock – most would shatter or crack if you tried to strike something hard with them. The best materials to make wood and stone working tools from are hard, dense minerals that have been forged in the high pressure and temperature of volcanic activity under certain chemical conditions. This kind of stuff doesn’t occur just anywhere – there are only a few places in New Zealand where ideal adze-making rock occurs on the surface and can be quarried, and often there may only be very small quantities of it available, making this material a valuable resource.
Each source will produce a distinctive and unique type of rock, and by looking at the colour and texture of the adze Richard was able to be pretty sure it was made from Tahanga basalt – a dark, dense rock found in only one location in the country – Tahanga Hill in the Opito region of the Coromandel Penninsula. It’s not that surprising that the stie at Wairau Bar should contain stone from hundreds of kilometres away – based on what has been found before it seems the people who lived here had already thoroughly explored the entire country and its mineral resources within a very short time of arriving. A whole range of “imported” rock types have been found at the settlement – obsidian from Mayor Island in the Bay of Plenty, argillite from D’Urville Island in the Cook Strait, chert from near Kaikoura, pumice from the Volcanic Plateau and perhaps the most sought-after of all – greenstone or pounamu from the West Coast. By using their twin-hulled sailing waka the tupuna would have been able to sail north or south up the coast, or paddle smaller waka up the Wairau River, and reach anywhere in New Zealand within quite a short time, bringing back cargoes of valuable minerals to make their tools from. They may even have established trade networks and had other iwi come to them to barter and exchange local commodities. All of this was possible within perhaps one generation of first reaching and settling in their new home.
After identifying the exact location the adze material had come from, Richard and Chris Jacomb began to tell me about the tool itself. Adzes are one of the main way archaeologists can trace the development of early culture – you can’t use carbon dating or any of those modern techniques to find out when it was made – any date you did get would of course be from when the rock itself was formed – likely to be many millions of years! However the shape and style of adzes does change over time, and is a useful way to estimate when they were made. This one is apparently a classic East Polynesian design – identical to ones found in areas like the Cook Islands from a similar period. Technically it’s known as a Type 1, meaning it’s quadrangular in shape (in other words the back is narrower than the face). A “tang” has been carved into the butt end – a narrower area to allow a wooden handle to be lashed on. We can even tell it had been used a lot because this area has been polished extra smooth by the flax fibres that were wrapped around the handle.
At the business end, other details of the adze can be determined. The blade has been deliberately made convex (that is, it curves outwards) to make the tool cut through wood more easily. An adze of this size was probably used for working and smoothing planks of timber, rather than detailed carving, and the convex shape and angle of the blade would have helped lift up woodchips and stop the tool getting stuck in the wood when it was swung like a pick-axe.
We can even predict that at some point, whoever used this tool was probably quite annoyed. There is a small chip out of one corner of the blade, and by looking closely the archaeologists can tell that this happened during use. There are very fine “shockwaves” in the rock exposed by the chip, radiating outwards from a single point right on the corner of the blade. This shows the impact that caused the chip came from the cutting edge, rather than any other part of the adze, and this must have happened while it was at work.
So just from one small adze, a whole story emerges. Some time around seven centuries ago, a block of basalt rock was quarried from Tahanga Hill in the Coromandel, and sailed down the East Coast to Wairau Bar. It was made into an adze, attached to a wooden handle, and used to shape timber and planks, for use in buildings and waka. At some point, the user swung it at a log, a small chip was knocked out of the blade, and they were probably not very happy that a favourite tool was ruined! Rather than repair or rework it, they decided to bury it in the foundations of a new building for spiritual protection or luck, where it lay for 700 years until last Saturday afternoon. Impressive!
This is just the beginning of what the excavations at Area 1 can tell us – I’ll be back soon with more.