Stone tools are a key aspect of prehistory. They are well preserved in the archaeological record and can tell us a lot about the technology and culture of hunter gatherer groups. Nowadays, we have plastic and metal – our knives, forks and scissors are all made of these materials. In the past what did we have? Well, among others (such as wood, bone or antler) we had stone.
But not all stone is good for making a stone tool, is it? Who can say they enjoy those tiny plastic forks that come with ready-to-eat salads and barely manage to carry any lettuce to our mouths? Likewise, in the past, poor quality stones would not be ideal for creating stone tools and shaping them to the hunter’s needs.
Quality matters. And that’s why we find a lot of stone tools made of chert. Chert is a fine rock, which allows for the knapper to create tools which are durable and sharp.
But where did hunter gatherers in Prehistory find quality chert? Let me give you a hint – not the supermarket. In the past, human groups travelled to places where they could find chert, or they traded raw materials with other groups. Understanding these raw materials is also a way to understand how these groups organized their economy and lives. Knowing where these raw materials came from is essential to understand how prehistoric humans used the landscape.
Here is where fieldwork comes into play.
During the first weeks of August, we visited the southwestern coast of Portugal in search of raw materials – namely, chert. The goal was to identify outcrops and sources of chert in this region and collect samples (fig.1). With suitable geochemical and petrological analysis, these samples can then be compared to stone tools found in the archaeological record.
We visited several outcrops, walked a lot and hammered on rocks even more. We drove through tiny dirt roads and got lost in the middle of wild, uncultivated fields. Well, it was an adventure. And the result? An amazing amount of different chert with a ton of variable colors such as yellow, grey, pink, purple or brown. Because most the outcrops are located near the sea, in beaches or cliffs, we were even able to witness some of the Algarve’s most breathtaking sights!
Fieldwork was a success, and now we can use the results to further understand how past humans used raw materials. Who says scientists need to make science solely inside a laboratory? Not us archaeologists, for sure.
Author: Joana Belmiro and Roxane Matias