201

Geoarchaeology and Archaeomineralogy (Eds. R. I. Kostov, B. Gaydarska, M. Gurova). 2008. Proceedings of the International Conference, 29-30 October 2008 Sofia, Publishing House “St. Ivan Rilski”, Sofia, 201-204.

ROCK-CUT STRUCTURES IN THE EASTERN RHODOPES AND THEIR RELATION TO PREHISTORIC MINING

Maria Zlatkova

Krakra Str. 8, 1504 Sofia; mariq_zlatkova@abv.bg

ABSTRACT. The presence of lot of unique trapezoidal rock-cut niches in the Eastern Rhodopes is linked to rich deposits of gold, silver and copper

in this region. Grouping of the rock recesses (niches) in rows and columns could be interpreted as a specific unique code. This “language” was

been used by the ancient miners during the Chalcolithic for saving and delivering the knowledge about their early mining activity.

The Eastern Rhodopes comprise approximately 4500 m2 of the territory of Bulgaria. This region is intensively erosively differentiated and characterized by middle, to alpine relief. The big rivers flowing through this region and their tributaries are deeply inserted into the generally round, hilly relief and, at some places they form narrow gorges. The Eastern Rhodopes ascended by the end of the Paleogene. In the volcanic rocks, both horizontally and vertically, multiple rock phenomena were formed, resembling figures, obelisks, rock mushrooms and stone pyramids (Fig. 1). In the Eastern Rhodopes mining region are known mainly gold-bearing lead-zinc deposits (Boyanov et al, 1992; 1995a; 1995b; 1995c).

During field works in this region, 39 features with trapezoidal recesses (niches) incised in the rocks (about 1250 in number

so far) have been explored and documented. The signs that are repeated in all of them are as follows: ▪ they exist only in the Eastern Rhodopes, and only in one limited region; ▪ they are made to be seen from a distance;

▪ they are made in rocks situated along the river valleys, so that to be easily visible from the routes used for traveling in the Antiquity; ▪ they are made at overhangs or beneath the rock peaks, so that they can be preserved for millennia; their interior is well smoothed, almost polished; ▪ in most of the cases, there are caves beneath them, different in size, or only rock shelters;

▪ in most of the cases, agate, opal, chalcedony and other semi-precious stones are found in the rivers beneath, (it is suggested that these are the richest rivers in gold in the region, and in situ gold deposits also are known in the area.

Fig. 1. Mushroom-like natural rock structures in the Eastern Rhodopes probably used as shelters in the past (near the village of Duzdovnitsa)

202

On the grounds of the 1250 already explored trapezoidal recesses in different rocks, that have different orientation, and are different in number and as situation, the following hypothesis about their nature and functional purpose can be suggested: during the Chalcolithic, the rock trapezoidal recesses are closely related to ancient mine works. There are traces of both open (quarry) extraction and underground mine galleries and shafts.

The region of the Eastern Rhodopes is considered to be scarcely populated during the Neolithic. The mountain is rich in deposits of gold, silver, as well as of precious and decorative stones. Prehistoric people used to find and explore these deposits. They used to climb up the mountain in order to extract and carry down to the valley the so important gold, silver, copper, etc. It was a seasonal work, during the summer month of the year and only temporary camps were erected close to the mines. The natural caves were very comfortable in this respect, adapted in the form of provisory shelters. Logically, most of the sherds and stone tools from the Chalcolithic Age have been found there. At 16 features,

Chalcolithic pottery has been registered. Many of the cave-like structures represent small mines shaped by man. They are mainly volcanic rocks and no natural caves can be formed there.

The trapezoidal recesses represent symbolic inscriptions where the knowledge of the ancient miners about mineral resources (gold, silver and copper), about the semi-precious stones and their deposits were written. The easiest place to extract them was along the rivers. It was along the rivers that the ancient peoples used for travel, coming from the valley and going to the mountain. As they were the first men occupied with mining, they had to learn from their experience and errors. That is why this knowledge was preserved by the means of inscriptions of the trapezoidal recesses, they had been overwritten and given to the next generations. It can be seen at once, that the recesses are ordered in lines and groups by number. The documentation regarding the position and number of niches is evidence that there are inscriptions which are repeated in different rocks, or that they are very similar at different sites (Fig. 2).

Fig. 2. Sketch-drawing of the position of groups of trapezoidal rock-cut niches in different sites in the Eastern Rhodopes

203

The prehistoric people living in the Thracian valley used to reach the Rhodope Mountain, to the South, via rivers. The grounds for such an assertion lay precisely on the rocks containing trapezoidal recesses: they are concentrated mainly in the Northwest area of the mountain (the hills of Dragoyna, Mechkovets, Karakula, and down the Borovitsa River valley) where they are the largest in number. The ancient miners worked also in the Arda River valley – on both its banks from the town of Ardino to the town of Madzharovo. To the North of Arda River explorations have also been made along the Perperek River, and to the South – down along Krumovitsa River to the town of Krumovgrad. At present, in the Southern area, on the line Krumovgrad – Momchilgrad, the trapezoidal recesses are almost missing, and to the East, up to the line from the village of Malko Gradishte (“The Deaf Stones” site) to the village of Senoklas, the last deposits to be explored before the abandonment of these areas (as it may be supposed) can be found. We must have in mind that few people were occupied with the extraction of gold and semi-precious stones during the Chalcolithic Age – maybe just a small group, or even a family, and they were the first miners. The trapezoidal recesses were their coded script, and the code was known only by the miners, who were able to read it. After the Chalcolithic people left these lands, this knowledge was not lost and the tribes that came later, the Thracians, rediscovered the deposits and continued their exploitation. There are written sources from 1500-1200 BC about the extraction of gold by the Thracians. The Thracians enlarged the extraction of gold and their mining works are spread almost throughout the whole mountain. The stone containers (“sharpani”) are another group of rock-cut monuments in the Eastern Rhodopes. A total number of 38 “sharpani” were explored and documented. They must not be discussed as a whole but should be analysed separately in the context of each site. Their purpose must be revealed by their functional signs. It can be supposed, that most of them served to crush and grind the ore, or to toss gold-bearing sands from the rivers (alluvial placers). Some of them have more day-to-day nature. There are two types of miners “sharpani”: composed by one recipient, and composed by two recipients. When they are composed by one recipient, they have semispherical shape and represent stone mortars to mill the ore. Often, they have chutes (spout) to drain out the water. The separation of the metal from the crushed rock mass takes place by gradual flushing-out of lighter particles. The material is sorted by water, and the heavy fraction settles to the bottom. The pure metal (gold, silver, copper) is mechanically separated from the dried sediment.

When it is composed by two recipients, the structure serves for flushing-out of both the already milled ore and the bulk ore deposits. Both recipients are connected by a narrow orifice, ending by a spout over the inferior recipient. The superior recipient presents a big, shallow basin, with even bottom, slightly inclined to the spout. At its upper end, one or two chutes are cut out, for water supply. Generally, one of its boards is lower than the other. By the help of enough quantity of water and being stired, the heavier fraction in the crushed

material drowns to the lower end of the basin and flows through the spout to the lower recipient. One or several overflows are perforated in it, at the level of the spout. The lighter fraction remains on the top of the basin and it is pushed our through the lower board. At the inferior, deep recipient, the heavy fraction is concentrated and the flushing-out process continues till it is full up to the overflows. Probably, after this process the heavy schlich is finally washed manually by a wooden bowl. Finally, it is dried and the desired metal is mechanically separated. This was, in general lines, the technology of the ancient miners to extract precious metals (Fig. 3).

Fig. 3. A rock-cut “sharpana” near the Borovitsa River, Eastern Rhodopes

Attention has to be paid to the tools and techniques used to make this recipient, to understand when they have been made. Some of them are very modern: they serve for wheat pounding, grape smashing, as water tanks and cattle drinking-pools, etc. It is important where they are located and what functional features are found on them, so that to make a link to one or another human activity or period. The rock sites “harmani” (“stack-yards”, threshing floors) are another rock-cut phenomenon. Three of them have been documented so far, in the region of Harman Kaya and in the region of the village of Tatul. It can be supposed they are platforms for kollergangs: stone wheel which serve to crush the ore. They have been moved using human or animal power, by a long rod around a central axe, like the wheat stack-yards. Very close to them, there are incised stone recipients of two beds connected with a spout, for further separation of the crushed material (Fig. 4). Other rock-cut structures can be observed in the rocks nearby, such as staircases, grooves, small pools and rounded holes on the surface of the rock, but they are single elements in the context of a certain deposit and must not be analysed separately. In the future, it is necessary to make full documentation regarding the deposits with rock incisions, involving specialists in the field of mining. A lot of work must be done in answering the questions who, when and why has cut these strange stone sites.

204

Fig. 4. The Harman Kaya rock-cut circle structure (kollergang) in the Eastern Rhodopes

References Boyanov, I., D. Kozhukharov, A. Goranov, E. Kozhukharova, M.

Russeva, Zh. Shilyafova. 1992. Explanatory Note to the Geological Map of Bulgaria 1:100000. Map Sheet Haskovo. Sofia (in Bulgarian).

Boyanov, I., D. Kozhukharov, A. Goranov, E. Kozhukharova. 1995a. Explanatory Note to the Geological Map of Bulgaria 1:100000. Map Sheet Krumovgrad and Sape. Sofia, 97 p. (in Bulgarian)

Boyanov, I., D. Kozhukharov, A. Goranov, E. Kozhukharova, M. Russeva, Zh. Shilyafova. 1995b. Explanatory Note to the Geological Map of Bulgaria 1:100000. Map Sheet Kurdjali. Sofia (in Bulgarian).

Boyanov, I., D. Kozhukharov, A. Goranov, M. Russeva, Zh. Shilyafova. 1995c. Explanatory Note to the Geological Map of Bulgaria 1:100000. Map Sheet Haskovo. Sofia (in Bulgarian).