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44 WŁODZIMIERZ WOJCIECHOWSKI

at Siciny distant about 100 kilomctrcs from Jańska Góra¹². To definc thcir eventual similarity to the ser-pentinite of which Jańska Góra is built or to exclude such similarity, researchers took 8 serpentinite samples from various points on that hill and carried out identical raw materiał tests in order to make a comparative ana-lysis.

Spectral tests, Chemical analyses and rcsults of pe-trographi studies indicated a great similarity between the raw materiał used in the production of implements and serpentinite not only from the generał regions of the eastern part of the Ślęża rangę (Gogo ów—Jordanów zonę) but also antigorite and carbonate exactly localized serpentinites sińce they compose Jańska Góra. This confirmed our conviction that the depressions found on the hill referred to may be ancient quarrics¹³.

Jańska Góra is of an absolute hight of 253 metres above sea level and rises in the surrounding area up to 80 metres and about 60 metres above the plateau on which the ncarest Funnel Beakcr Culture settlement at Janówek was situated; clcarly outlined in the terrain it rises about 40 kilometres south of Wrocław and in the south-eastern dircction of the Ślęża pcak on that area belonging to the Łagiewniki Administration, bet-wecn (fig.8) Janówek (in the north), Piotrówek (west-wards) and Sokolniki (in the south). This elevation (fig.9) is, at present, compared with its original State, considerably changed, primarily by human activity at the end of the 19th cent. and the beginnings of the 20th cent. and by activities during World War II.

The smali field on which researchers identified the vow of depressions resembling extraction pits is situated on the north-western upper part of the slope, it is about 2 metres beneath the top. The field covers an area of about 300 sq.m.

Out of four funncl-shapcd depressions arranged in a row, marked from the north with numbers from 1 to 4, the two northern pits, marked 1 and 2, have been cho-sen for investigations. This choice was decided by the fact that although they are close to each other, they difier, above all, in size (fig. 10).

The funnel-shaped pit no.l (farthest to the north) was — in horizontal projection — of a circular form slightly elongated to the south. The horizontal dimen-sions, calculatcd from the contourlinc “0” determining its edge, were 7.20 metres along the north-south axis and 6.60 metres along the east-west axis. The walls of this funnel came down archwise towards the bottom at 1.02 metres in relation to the contourlinc “0”. The bottom of this funnel-shaped pit is levelled out.

The upper edge of the second funnel-shaped pit (to the south of pit no. 1) is of an equally circular shape. Its diameter, measured on the contourlinc “0”, is 3.40 metres. Its inner walls descend evenly to the channclled bottom at a depth of 0.43 metres. This pit is surrounded by a slightly perceptible circular embankment 1.50 metres wide at the base and 0.12 to 0.22 metres high.

The distance between the two pits is 1.50 metres (fig. 11).

Assuming that the diffcrences in the size of the two pits could have resulted from the use of various ex-ploitation techniqucs or difierences in the intensity (scalę) of exploitation and, in order to make it possible to compare the elements of the two extraction pits, the two objects were joined by a common excavation.

Summung up observations madę during cxcavation researches discovercd:

1.    An obvious post-extraction site in pit no. 2. This was provcd by negatives from extracted regular serpentinite blocks. The extraction pit was filled with weathered rubble disorderly mixed with loamy humus (fig. 14).

2.    A zonę of serpentinite rock of a smooth, natural surface without signs of exploitation adjoining from the north the cxtraction site beneath pit no. 2 (fig.17). This zonę, 1.20 to 2.50 metres wide separated extrac-tion pits no.2 from pit no.l.

3.    Further to the north the zonę with a natural surface passes through an cxtraction downeast into bcd-rock descending stepwise to the north towards the deepest part of funnel no.l. There are numerous ncgatives from cxtracted raw materiał on the surface (fig.20). The deepest zonę with exploitation traces is situated beneath the deepest part of funnel no.l (fig.21).

4.    Further to the north the bed-rock disappears into a natural depression. Above this zonę there appeared the northern part of the wastc-heap which was disco-vered in the direct vicinity of funnel no.l on the western and eastern sides as well.

5.    Under the eastern and western waste-heap there appeared a strongly weathered rock-bed without traccs of cxploitation.

Reconstructing the course of the exploitation pro-cess on the basis of extant traces, we have found that after the removal of a smali layer of smali degraded rock rubble, it was not loosc rock fragments occurring in loam which were exploited, but solid rock crackcd in a natural way so that it parted into regular rectan-gular blocks of maximum dimensions 30-35 by 10-15 by 10-15 centimetres. Such blocks were the rcquired form of raw materiał. Unsplit, solid rock was not quar-ried.

During a strict selection of the extracted materiał deformed blocks were discarded on the waste-heap. The sclected materiał was taken from the pits to settle-ments for further treatment.

There is the question, howcver, if the discovercd and recognized objects should be defined as mining pits. If we accept the definition of “mining” as proposed