On the site

We went to meet Mariana Petry Cabral and João Darcy de Moura Saldanha on site. The two archaeologists from the Institute for Scientific and Technological Research in Amapá (IEPA) were busy excavating. Beneath the shelter of a large tent, they were unearthing a ditch where bits of pottery could be seen poking up through the soil. Around them, five young students were learning how to dig, record, draw, and interpret.

To give a rapid description of the site at Calçoene: it is a circular alignment of about 100 granite menhirs, some upright, some lying down, at the top of a green hill. In Europe, this sort of stone circle is called a cromlech. The most famous is Stonehenge in England, but other examples of this sort of megalithic group can be found dotted all over the world – such as Gobekli Tepe in Turkey, Ikom in Nigeria, and Almendres in Portugal. Nevertheless, no link has been established between these sites other than their ability to fire up curiosity.

We are no strangers to this and arrive on site brimming with questions. Mariana and João had some answers. Despite being tired, they good-naturedly and enthusiastically took the time to tell us the story of the stone circle of Calçoene.

Interview with Mariana Petry Cabral and João Darcy de Moura Saldanha

The archaeological site is in the Brazilian state of Amapa, roughly ten kilometres from Calçoene, on the edge of a trail linking this old mining town with the village of Counani. Whilst the spot is well-known amongst the inhabitants of the region and a few curious travellers, its recent discovery within the media and the scientific community is thanks to two researchers at the IEPA. A botanist and meteorologist came across it whilst looking for deposits of granite and alerted the Government of Amapa.

The State government immediately understood the (mainly tourist) potential of the site and took the appropriate measures to protect it. The land was bought by the Brazilian Ministry of Culture and the site was officially opened in 2006.

Mariana and João admit that they have been very lucky. Recent graduates from the Federal University of Rio Grande do Sul (Porto Alegre), they had just got jobs in Macapa at the time. Excavating a site such as this is a dream for any archaeologist.

First of all, the research zone was carefully demarcated and mapped. In particular, it was established that the hill on which the stones are erected is a natural geological formation. The entire site was then prospected in the search of any traces of human presence apparent in the ground (stones, tools, ceramics, and so on). The next phase consisted of carrying out several surveys by excavating small areas in carefully chosen spots so as to better target the most interesting areas for the study.

The first real archaeological dig started in August 2006. The archaeologists have been returning regularly ever since, working at the site fifteen or twenty days a month. They estimate that they have so far excavated about 15% of the total surface of the site.

Granite Dominos

Whilst the Calçoene archaeological site is not as monumental as Stonehenge, it is imposing nonetheless. The stone circle is no less than thirty metres across and is made up of about one hundred blocks of granite, the tallest of which are over three metres. It is certainly a compelling sight.

Once you have recovered from your initial reaction, the stone circle gives the impression of having been ravaged by time and the elements. Many stones lie on the ground, and some blocks of granite seem to be arranged like dominos, ready to topple.

The research of the archaeologists, however, suggests that this is not the case. They explained to us that most of the stones were cut and then carefully erected just as they stand today. Those lying on the ground never stood upright. Instead, the layer of laterite was carefully dug so that they fit snugly with the ground. Excavations carried out in 2006 around the bottom of the standing stones also revealed small blocks of granite and laterite which were used to wedge the monoliths at this unusual angle. By comparing the first photographs taken of the site in 1920 with those taken in 1950, the archaeologists noticed that the blocks had not moved at all. On a part of the site, according to them, the stones are still as they were initially set up, and some of the stones were deliberately positioned at this angle.


Within the stone circle, the team of archaeologists have unearthed two burial pits, two and three metres deep. Both contain a large number of ceramics, some of which are still intact. Some recipients still contain some charred bone. Each pit was carefully sealed with a large slab of granite.

In addition to the hypothesis that it was a burial site, another possibility has been suggested by one of their colleagues from IEPA who noticed during the afternoon of the 2005 solstice that the North and South faces of one of the blocks of granite were illuminated simultaneously, without any shade whatsoever. Other indications pointing in the same direction have been found by the archaeologists, although they are cautious about proposing any theories and therefore have not included this hypothesis within their research plan.

Whilst most megalithic sites of this sort have given rise to numerous interpretations, the most frequent is that they were used as astronomical observatories. However, nothing has been proven to support or invalidate this hypothesis. The stone circles are still shrouded in mystery and speculation.

Who, when, and how?

“Who, when, and how?” are the three questions the archaeologists told us that they were trying to answer. They point out that very little has been written about this kind of collection and it is only in French Guiana that archaeology is beginning to provide some elements for comparison (see the article about the Pointe Morne site in this special report).

Archaeology in Amapa has only just started and the researchers admit that they know basically nothing about settlement in the area. They explained that the most standard theory of settlement is that Amerindian people from the Caribbean zone came to the region (in the Arnã phase) before being chased out by a second wave of migration (the Aristé phase). Without seeking to undermine this chronology, the two researchers think that it is also possible to put forward a second hypothesis, according to which a group emerged locally with an as yet unspecified zone of influence. The megalithic sites seem to be specific to this region. The archaeologists point out that a large and relatively well organised population would have been required to build and install this type of monument.

The chronology of the site – the period when the monument was built and used – is also difficult to pin down. Excavation of one of the burial pits has shown that it was reused, which complicates the archaeologists’ task. It means that there were at least two periods when this place was used, one corresponding to when it was built and another later on when it was used by a different human group.

Currently, the only carbon-14 dating that has been carried out is on the charcoal associated with the ceramics, giving a chronological range of between 950 and 1000 AD.

The future of the past

The Government of the State of Amapa now wishes to open up this protected area to tourism. The idea is to set up a small research laboratory on site, which could be used to train students, and an archaeological circuit. The potential for tourist facilities in this zone is as yet uncertain. Whilst the stone circle is the largest and best conserved, it is not unique. Archaeological excavations carried out in the region have shown just how many megalithic sites there are in northern Amapa.

Mariana and João are now thinking of the next stage, locating and excavating a dwelling associated with one of these megalithic sites. As they explain this with a glint in their eyes, it is clear that this voyage into the Amerindian past of Amapa is far from being the last.