Tag Archives: Axe grinding grooves

When is a groove formed by axe grinding?

Hi again groovers! Can you work out which of the following are axe grinding grooves amongst the pictures below?

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1

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2

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3  

(Images courtesy of Lynley Wallis)

To be certain we need some measurements!

Perhaps just like you as I started this investigation I thought “seen one groove, seen them all”- not so! In fact it emerges that various kinds of grooves were made by Indigenous people and that they had differing uses, including spear sharpening, ochre grinding for pigment production and seed grinding.

So how can we tell an axe grinding groove from a groove used for some other purpose, or even from a naturally occurring groove? It’s not always easy but according to the experiments over 15 years of one prominent expert, F.P. Dickson, all axe grinding grooves share certain similarities. Dickson even came up with ranges of dimensions of grooves that are suitable for axe grinding and argues that other sized grooves were unsuited for this purpose and thus reflect different usage.

So what are the dimensions characteristic of axe grinding grooves? Dickson found that they were typically 25–50 cm in length, 5–8 cm in width and 2–4cm deep at mid-length. There does exist, however, some scope for difference and margin of error; while some studies have corroborated Dickson’s findings, others have categorised grooves as axe grinding ones even when they do not fit within these parameters. In practice, there is usually some degree of subjectivity between different researchers about what constitutes the exact edge, ridge or mid-point of the groove.

As always in archaeology the contexts in which artefacts occur are crucial for providing accurate information. Axe grinding requires a substantial amount of water to act as lubricant so most axe grinding grooves are found near water sources. They also need just the right kind of hardness of rock surface, with sandstone the most suitable, typically along creek and river margins. They can also be found in rockshelters but here they will usually be fewer in number, depending largely on water and suitable surface availability.

As for natural grooves that might be mistaken for axe grinding grooves, they’re usually fairly broad, shapeless and shallow. So the first and third pictures above are of axe grinding grooves, while that in the middle is of a grinding surface used for some other purpose, perhaps seed grinding!

Now it’s “back to the grind” for me – keep an eye on this blog in the near future for a look at some of the edge-ground axes that made these grooves!

And for those of you who want to learn more about Dickson’s seminal research into axe grinding grooves, here are the references for his key papers on the topic:

Dickson, F.P. 1976 Australian ground stone hatchets: Their design and dynamics. Australian Archaeology 5:33–38.

Dickson, F.P. 1980 Making ground stone tools. Archaeology and Physical Anthropology in Oceania 15:162–167.

Dickson, F.P. 1981 Australian Stone Hatchets: A Study in Design and Dynamics. Sydney: Academic Press.

Get Grooving!

Everyone knows about boomerangs and spears- and many members of the general public are pretty familiar with flakes and cores (even if they don’t know the technical terms for them and call them “funny looking rocks”). Archaeologists are happy about our adzes, tulas and backed blades, and extensive research has been done about these sorts of artefacts and what they can tell us about past human behaviour.

But what of axe-grinding grooves? What can these features tell us of the past? What is currently known about them and how much research has focused on them? The answer is, not a lot! Perhaps this is because they are ubiquitous in many parts of Australia- especially in sandstone areas- and their function (axe-grinding) is obvious (although other grooves exist that were used for different purposes like seed grinding or ochre grinding).

Yet perhaps there is more to learn from them.  What can be discerned from their dimensions (length, width, depth and orientation)? Can these reveal some patterns in the axe-grinding grooves’ usage and suggest related reasons?

Now, thanks to my kind Industry Partner, Lynley Wallis from Wallis Heritage Consulting, these are some of the questions that I have the chance to explore.

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Students measuring axe-grinding grooves at Middle Park Station using an offset surveying technique (image courtesy of Lynley Wallis).

To do so I will review what we know about axe-grinding grooves in the sandstone belt of north-western Queensland, followed by investigation of a case study involving the Rocks Cross Axe Grinding Site, approximately 120km north of the Richmond township.

Armed with measurements of hundreds of grooves, site plans and an imminent crash course in Adobe Illustrator for electronically compiling the latter, I will keep you abreast of my progress as I attempt to unlock some of the secrets of these hitherto under-studied archaeological features.