Comparing Prehistoric Art in 3D: A New Archaeology Tool

I've spent years examining flint tools and other prehistoric stones for signs of intentional imagery. One problem has always stood out: photographs can only show so much.

There is so much to see in this palaeolithic handaxe, but I thought I would just show you the elephant front half, a glyph I've been banging on about for almost 15 years.

You might see an animal's head in one photograph, a facial profile in another, or a particularly interesting arrangement of flake scars. But how do you compare those features properly when the objects are in different collections, photographed from different angles, or located hundreds of miles apart?

And what if you want to examine the other side of the stone?

This is something I've wanted to address for some time. I've now developed a 3D archaeological artefact comparison workspace on Eoliths.org, bringing several interactive models together on one screen.

It's a fairly simple idea, but I think it has considerable potential for research into prehistoric figuration, stone-working techniques, portable rock art and the possible origins of visual communication.

Try the 3D Archaeological Comparison Workspace on Eoliths.org

Six 3D models, side by side

The workspace opens with six archaeological objects displayed in a grid of three across and two down on a desktop computer.

These aren't just photographs. They're interactive 3D scans that you can turn, tilt and zoom in on.

Each window has its own model selector, allowing you to replace the object with another from the available collection. You can compare two different handaxes or, just as usefully, display the same handaxe in two windows and examine different faces or viewing angles at the same time.

I've also included a small control to fold away the descriptive text beneath each model. That leaves a much cleaner screen when you want to concentrate on the actual stones.

The starting collection consists of Lower Palaeolithic flint artefacts digitised by James M. Hicks and published by 3Djimmetry on Sketchfab. I've retained the links and attribution to the original scans.

But the important development isn't simply having six models on the page. It's being able to choose which objects to compare and then examine them independently.

Why this could matter for prehistoric art research

Imagine finding what appears to be an elephant's head worked into a flint tool.

You can see a trunk, an eye and perhaps a distinctive bump above the forehead. The boundaries of flake removals appear to form parts of the anatomy.

You might be convinced that the image was intentional. Someone else might dismiss it as coincidence.

A photograph alone isn't necessarily going to settle that disagreement.

Now imagine finding several more artefacts with similar arrangements. Perhaps the head shape recurs. Perhaps the eyes occupy corresponding positions. Perhaps the same anatomical divisions are formed by intersecting flake scars, with small pecked details appearing in similar places.

At that point, we're no longer talking about one stone that happens to resemble an animal. We're investigating a recurring combination of visual and technological features across an assemblage.

That is potentially much stronger evidence.

My research has led me to propose that some prehistoric people incorporated recognisable subjects and repeated visual devices into their stone-working. These include animal profiles, human and ape-like faces, hands, fingers and geometric marks.

I have described this possibility as a form of prehistoric visual communication.

The challenge has always been demonstrating that the patterns are genuinely repeated and physically constructed, rather than simply recognised by an observer.

Being able to put several artefacts together and examine their actual three-dimensional surfaces offers a useful way forward.

Looking beyond the outline

One of the things I find particularly important is how an image has been made.

If a proposed animal figure is present, what actually defines it?

Is the line of the back formed by a deliberate flake removal? Does an intersecting scar form the jaw or neck? Is a small indentation positioned where an eye would be expected? Is there a relationship between the working sequence and the final appearance?

These are questions that deserve more attention than they usually receive.

A recognisable outline is a starting point. But when an outline is supported by consistent anatomical details, repeated technical interventions and comparable examples from other stones, the argument becomes much more substantial.

This is closely related to the Stacked Constraints approach I've described elsewhere on Eoliths.org. Rather than depending on one striking resemblance, I look for several independent lines of evidence that support the same interpretation.

The new workspace makes it easier to study those relationships directly.

It can also expose weaknesses in an interpretation. A feature that looks persuasive from the front might turn out to be a normal fracture boundary when viewed from the side. Another feature might become clearer once the model is rotated.

Either result is useful.

Try comparing the same stone from two angles

This is one of my favourite uses of the workspace.

Choose the same artefact in two adjacent windows. Rotate one model to show its broad face, then turn the other to reveal the opposite face or an edge-on view.

You can examine how the flake scars relate to one another, whether a proposed figure has any depth, and whether a particular feature belongs to the original stone surface or a later removal.

Then try a second artefact displaying a similar feature.

Do the anatomical relationships correspond? Are the same kinds of marks involved? Does the image depend on a very particular angle, or is its structure still understandable as the stone is turned?

These are the sorts of comparisons I want to encourage.

There are perfectly ordinary technological questions to investigate as well: edge preparation, bifacial working, cortex retention, symmetry, tool thickness and possible differences between manufacturing traditions.

The workspace isn't restricted to figurative interpretations.

You can bring your own artefacts into the comparison

This is where I think the project could become particularly interesting.

Suppose you've found an unusual worked stone or you're studying a museum object that appears to contain deliberate imagery.

If you can obtain a suitable 3D scan, you may be able to compare it directly with archaeological models already available online.

There are several ways of recording an object in three dimensions. Photogrammetry uses overlapping photographs to reconstruct its surface, while structured-light scanners can capture detailed shape and texture information.

Once your model is prepared and uploaded to Sketchfab with embedding enabled, its model link can be added to the Eoliths.org comparison workspace.

You could then place your own find alongside another artefact and examine both independently.

Of course, the quality of the scan matters. Poor lighting, missing surface detail or inaccurate textures can be misleading, particularly when you're investigating fine pecking, possible pigment or subtle flake boundaries. A recorded scale is also important for meaningful measurements.

And naturally, anyone scanning or publishing an archaeological object needs the appropriate permission.

But the basic possibility is there: researchers and collectors could compare their own documented artefacts with material held elsewhere, without needing the physical objects together in one place.

The workspace does not identify motifs automatically. That's not its purpose. It gives people the means to inspect and compare the evidence themselves.

The Goodwood handaxe and a possible elephant figure

One example I've included on the Eoliths.org page is a Goodwood handaxe with unusually thick white patination.

I see what appears to be an elephant front half figure worked into this object. The interpretation involves the arrangement of flake scars, the lines where those scars meet, and small details that appear to help define the anatomy, no surprises here with this glyph, it's on my chart, just like other things visible here.

I've drawn around the proposed figure in an illustration so visitors can see exactly what I'm referring to.

A feature I find especially interesting is the distinctive bump on the animal's head. I've observed comparable shapes in other stones discussed in my research on prehistoric manuports.

Is this a recurring convention? Is the similarity significant? Are the apparent anatomical features deliberately constructed?

These are precisely the questions that comparative 3D examination can help us investigate.

Rather than asking readers simply to accept my interpretation, I want them to look at the surfaces and decide which features they can independently recognise and verify.

Not just handaxes

Although the first models come from a collection of ancient flint tools, I see no reason why the same approach couldn't be used much more widely.

Possible figure stones, selected natural objects, portable sculptures, engraved artefacts, worked pebbles and other archaeological materials could all be examined in this way, provided suitable scans are available.

For researchers interested in prehistoric cognition, that opens an intriguing possibility.

Could certain subjects or visual conventions have appeared repeatedly across different assemblages? Could some of the same methods of constructing imagery be recognised in objects made in different places or periods?

Those are big questions, and I wouldn't expect a single comparison to answer them.

But a growing body of accessible, well-documented 3D material could make them much easier to investigate systematically.

It would also make it easier for researchers to disagree constructively. Instead of arguing over a single photograph, they could identify the exact physical feature under discussion, rotate the same specimen and compare it with other examples.

An invitation to look for yourself

I've been documenting what I consider to be recurring imagery and visual conventions in prehistoric stone artefacts for many years.

This new comparison workspace is another step in that research. It gives me a better way to examine the material, but just as importantly, it allows other people to look for themselves.

Perhaps you'll recognise an animal figure I haven't noticed. Perhaps you'll identify a repeated arrangement of flake scars that deserves closer attention. Or perhaps you'll find a perfectly ordinary technological explanation for something that initially appeared figurative.

All of those observations could contribute to a better understanding of the material.

What matters is whether we can identify repeated, recognisable features and demonstrate how they were formed.

If you're interested in prehistoric art, ancient technology, portable rock art or the beginnings of human visual communication, I hope you'll give it a try.

Open the Eoliths.org 3D Archaeological Artefact Comparison Workspace

You can also read more about my approach to identifying intentional imagery on the Portable Rock Art Identification page, or explore the wider evidence on Science and Methods.

Brett Martin - Eoliths.org

The comparison workspace and associated interpretations are part of my independent research. Original 3D archaeological scans remain credited to their respective creators and publishers.