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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, 116-119.

PETROGRAPHIC STUDY OF ARTEFACTS FROM A TEMPLE OF SABAZIOS IN THE VILLAGE OF POROMINOVO, KYUSTENDIL DISTRICT, WESTERN BULGARIA Petya Nenova1, Oleg Vitov1, Ivanka Staikova2, Lydia Staikova Alexandrova2

1Central Laboratory of Mineralogy and Crystallography “Acad. Ivan Kostov”, Bulgarian Academy of Sciences, 1113 Sofia; petya_clmk@dir.bg; vitov@abv.bg 2Regional Historical Museum “Acad. Yordan Ivanov”, 2500 Kyustendil; rmuseum.kn@mail.bg

ABSTRACT. Stone artefacts from a temple of Sabazios, dated to the II-III c. AD by inscriptions, were uncovered during excavation at the “Zlatkova Vodenica” site, near the village of Porominovo, Kyustendil District. The petrographic study carried out on stone fragments from the Sabazios temple showed that the blocks of coarse-grained, fine-grained and hydrothermally altered granites originate from the slopes of the West Rila mountain – the water-catchment basin of the Rilska River was the source for construction material used in the Sabazios temple. These granites are unsuitable for quarry production and construction due to tectonic impacts and weathering. It is concluded that the stone fragments from the Sabazios temple are made of granitic blocks from fluvial-glacial sediments (boulders) in the region and that there are no evidence to suggest a quarry production. The travertine find is an indicator of the closeness of the Sabazios temple to the excavation site in the village of Porominovo.

Introduction

The village of Porominovo is located on both banks of the Rilska River between the towns of Kocherinovo and Rila, Kyustendil District. There are many artefacts in the vicinity of Porominovo as well as in the whole valley of the Rilska River, which give evidence for Thracian and Roman occupations in the valley – necropolises, fragments of massive buildings, pottery and stone sarcophagi. Stone plates (of syenite?) with a dedication to Sabazios were found in the vicinity of the town of Rila. The well known researcher of antique history and archaeology of the valley of Rilska River Gerov (1961) thought there was a sanctuary of this God there. The cult to Sabazios originates from the Thracian-Phrygian antiquity. Sabazios is a rock God and Phrygia is the land of his origin. He is an alternative of Dionysus. Sabazios is the sunny side, the Cosmos. He is the supreme God – Cosmocrator. During the Late Hellenistic period and the Antoniis and the Severian periods he was identified with Zeus-Jupiter. The Sabazios temples were astronomic observatories and teaching centres. Sabazios has no image and in the temples his personification is represented as a human hand made of metal, wood or stone on the base with inscriptions.

During rescue excavation in the village of Porominovo (Staikova, 2006) a monument with dedication to Sabazios has been found (II c. AD; Fig. 1). This artefact in combination with the abundance of stone fragments from massive, representative antique building is an evidence that the Sabazios temple has been located in the vicinity of Porominovo but not in the vicinity of the town of Rila as the previous researchers have supposed. The massive building has been constructed by rock pieces of granite and its varieties. The material used for columns of a 6-8 m height was

about some cubic meters solid rocks without defects and fractures. Such a material lacks in the vicinity of Porominovo, the valley of the Rilska River and the slopes of the Rila Mountain.

The present paper discusses a petrographic study of the materials which compose the antique building in the village of Porominovo in order to determine their rock composition, primary deposits and possible future prospecting for quarries of such solid material.

Fig. 1. Monument with a dedication to the God Sabazios

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Archaeological excavation

In 1983 in the foundations for a new building in “Zlatkova Vodenica” site, located at the crossroad on the right bank of the Rilska River in the village of Porominovo, stones of an unknown antique building were excavated (Fig. 2). In 1986-1987 some rescue excavation was carried out there as the Southwestern corner of an antique building was uncovered composed of re-used granite details. Two stone monuments with inscriptions in old Greek were documented. The first inscription is a dedication to Sabazios; the second one is hewn into the foundation stone and is not well preserved but “cyurioi Dii” (“to the Lord Zeus”) could be read in the first row. Both stone monuments are suggested to be artefacts from the Sabazios temple. In 1986 a borehole was drilled in a next site named “Kalaidziiskata Vodenica” and a Roman coin from the I c. AD minted in the town of Philippe was found in a culture stratum from the Ottoman period and the Bulgarian Upraise period together with a silver Ottoman coin. In August-September 2006 an organization was initiated for studying the “Zlatkova Vodenica” site. The carried out excavation showed that the feature has rectangular shape, with perfect North-South orientation and a size of 7.2х11.8 m. The foundations lay at depth of 1.8 m. The construction of the inner face of the 1 m thick walls consists of stone plinth and superstructure of non-worked boulders. The stone plinth which is 1 m high includes three rows of stone blocks of antique spolias and natural stone pieces. The space between the constructive details is significant and is filled with ballast and fragments of roof-tiles and pottery from XVII-XX c. AD. The superstructure and the facade of the walls are cemented with mud. The stone construction is laid on a massive wooden base made of coniferous boards 5х0.32х0.12 m in size. In the board below the Northern wall a bed is hewn for the stone blocks, which form three lines oriented in North-South direction. The wooden base is laid on a grey-greenish slime sediment layer 15-20 cm thick without archaeological finds and artefacts. Under it ochre-red clayey-sandy, poorly consolidated Neogene sediments of the Blagoevgrad graben crop out. The feature has a wooden floor, which now is 1.4 m below the modern level. The boards are laid lengthwise to North-South and are 5.30х0.32х0.07 m in size. Three wooden stakes in three lines oriented North-South are raised in front of the three blocks of the Northern wall and in front of the foundation stones to the South. The stakes are 30х30 cm in a cross-section. The fill of the building is a ballast of sand and gravel of ochre colour containing numerous corroded iron objects coated with gravel and sand clasts. In the ballast layer a lot of roof-tiles fragments and pottery of XVII c. AD were found among which a sgraffito plate. The southern wall consists of three granitic details of 1.40 m in height. Above each of them the facing structure is arranged in East-West direction by two granite blocks as the space between them is filled with non-worked stones. According to oral information at this level a wooden floor of water-mill was built there during the Ottoman period that existed till the middle of XX c. After that, in the 1960s, the building was used as blacksmith workshop.

Petrographic study After inspection of fragments from the antique building typical rock varieties were collected and hand specimens (5x5x5 cm) for petrographic study were hammered.

Fig. 2. Archaeological excavation at the “Zlatkova Vodenica” site in the village of Porominovo, Kyustendil District

The hand specimens were well consolidated. Rock slabs of around 3 cm2 in area were then prepared by cutting machine and consequent grounding with abrasives to around 0.03 mm in thickness. Every rock slab was glued on a glass slide with Canadian balsam and coated with a laboratory glass. The petrographical study was made by “Jenapol” petrographic optical microscope (Carl Zeiss Jena) under plain polarized light and crossed polarizers (Nicol prisms).

Hand specimen N1. Archaeological site – the village of Porominovo, Kyustendil District. Field determination: fine-grained granite. Type of rock: fine-grained porphyric granite. Macroscopically it is a grey-green fine crystalline rock with a massive texture (Fig. 3). Texture: porphyric by quartz, plagioclase, potassium feldspar and biotite, of ground mass – felsitic. Mineral composition: main minerals in the porphyries – quartz, plagioclase, potassium feldspar and biotite; in the ground mass – the same minerals, unevenly and not well crystallized. Accessory minerals: ore mineral, apatite, zircon. Secondary minerals: cryptocrystalline clay minerals and hydromicas, sericite, chlorite, epidote, rutile and ore mineral. Porphyres: quartz forms irregular or rounded crystals, fractured; its outlines are uneven. It is most often clear but sometimes is muddy due to cryptocrystalline clay minerals. The quartz includes ore grains, biotite flakes and prismatic to acicular zircon crystals. The plagioclase forms short prismatic to platy crystals. Most often it is lamellar, zonal. It includes small euhedral apatite crystals. The potassium feldspar is zonal, with prismatic crystals, sometimes of isometric outlines. At places cryptocrystalline clay minerals, hydromicas, and microcrystalline sericite are developed in it. Its boundaries with the ground mass are often corrosive. It includes ore mineral inclusions (groups of several crystals) and contains isometric to oval amygdalae filled with chlorite (penninite), clay mineral, ore grains and apatite. The biotite is brown, coarse to fine flaky.

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Fig. 3. Fine-grained porphyric granite from archaeological excavation in the villlage of Porominovo, Kyustendil District (a) and microphotographs: under parallel Nicols (II N) and under crossed Nicols (+ N), 100x

Sometimes it includes small sericite flakes and ore grains. At places it is transformed peripherally into chlorite or includes rutile grains, needles and “stars”. The ground mass is represented by small crystals of the mentioned above minerals as quartz, plagioclase, potassium feldspar, biotite and scarce ore ones. At places it is muddy due to clay minerals. Scarce epidote crystals also occur. The ground mass is unevenly and poorly crystallized as a whole. Accessory minerals: ore mineral with small, euhedral, rarely irregular crystals, at places in aggregates. Apatite is scarce, of euhedral small prismatic crystals. Zircon with small euhedral crystals is rarer than apatite. The studied granite has undergone weak hydrothermal and supergene alteration.

Hand specimen N2. Archaeological site – the village of Porominovo, Kyustendil District. Field determination: porous calcareous rock. Kind of rock: travertine. Macroscopic description: light beige fine-grained rock with many cavities. The cavities have almost circular cross-sections as well as lengthwise sections of oval and rectangular shape. Irregular cavities also exist. The cavities probably are result of already decayed plants or of paths of worms. The rock is light and effervesces in the presence of weak hydrochloric acid thus suggesting that is composed of carbonate mineral(s), most probably of calcite. Its structure is porous (Fig. 4).

Fig 4. Travertine from archaeological excavation in the villlage of Porominovo, Kyustendil district: macro- (a) and microphotographs: under parallel Nicols (II N) and crossed Nicols ( +N), 100x.

The rock texture is subhedral in respect to calcite, which is

the major mineral. Calcite is variable in size of isometric, more rarely of rhombic outlines. The coarser calcite grains are aggregated in nests, bands and lens-like concentrations. Calcite most often is water-clear with well expressed perfect cleavage but some crystals are muddy due to clay minerals or ore inclusions. The ore grains are scarce and of isometric shape. There are pores and lithoclasts irregular in size in the rock. Composition of the lithoclasts: they have unvaried composition and are represented by sandstones composed of quartz, plagioclase, potassium feldspar, biotite, muscovite, amphibole, glauconite, apatite?, epidote, ore mineral, clasts of quartzite. The cement of sandstones is clayey to clayey with iron hydroxides. The pores of lithoclasts are small of a circular, oval and most often of an irregular shape. Some of them are filled with clay minerals, iron hydroxides and oxides.

Hand specimen N3. Archaeological site – the village of Porominovo, Kyustendil District. Field determination: hydrothermally altered granite. Kind of rock: intensively altered granite. Macroscopically it is a grey-pink middle-grained,

jointed, cataclased rock. The joints are parallel to subparallel (Fig. 5).

Fig. 5. Intensively altered granite from archaeological excavation in the village of Porominovo, Kyustendil district: macro- (а) and microphotographs: under parallel Nicols (II N) and crossed Nicols (+N), 100x.

Structure: parallel to the secondary jointing. Texture:

cataclased; relict subhedral to anhedral and poikilitic. Primary mineral composition: potassium feldspar, plagioclase, intensively altered mineral (biotite? or muscovite?) and quartz. Accessory minerals: ore mineral, apatite (altered), zircon and titanite. Secondary minerals: quartz, ore minerals, epidote, clay and hydromicas minerals. The potassium feldspar is intensively altered by clay minerals and hydromicas. The joints cross-cutting it are filled with clay minerals and quartz. Its subhedral to anhedral crystals include poikilitically quartz (of irregular or isometric water-clear crystals) and completely altered maphic mineral of prismatic outlines, which is altered by hydromicas, epidote and ore mineral. The plagioclase is completely altered having only relict outlines as the polysynthetic twinning is deleted. The alteration is by clay minerals and hydromicas. Primary quartz is water-clear, of clear boundaries and isometric or irregular outlines. The accessory ore mineral forms small irregular to isometric grains and aggregates and most often is included in the potassium feldspar. The apatite is of small size forming short-prismatic outlines; it is altered by clay minerals. The zircon is also of short-prismatic outlines, of small size, scarce, at places of long-prismatic habits. Small euhedral rhomboid titanite crystals are also present. Relics of the primary rock are embraced by anhedral quartz mass containing single ore grains and aggregates. The primary rock and the embracing quartz are cross-cut by later quartz veinlets containing clay and ore minerals. Kind of metasomatic alteration: most probably argillization. Note: the relics of primary rock show a similarity with hand specimen N 4, described as biotite granite.

Hand specimen N4. Archaeological site – the village of Porominovo, Kyustendil District. Field determination: coarse-grained granite. Kind of rock: biotite granite. Macroscopically it is pale grey-white coarse-crystalline rock of a massive texture (Fig. 6).

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Fig. 6. Biotite granite from a column’s base (archaeological excavation in the village of Porominovo, Kyustendil District): macroscopic outlook (left, а) and microphotographs (right) under parallel Nicols (II N) and crossed Nicols (+ N), 100x

Texture: subhedral and poikilitic in respect to potassium feldspar and included in it quartz, plagioclase and biotite. Mineral composition: potassium feldspar, quartz, plagioclase and biotite. Accessory minerals: ore mineral, titanite, apatite and zircon. Secondary minerals: cryptocrystalline clays and hydromicas, sericite, chlorite, epidote and ore mineral. The potassium feldspar is very well represented. It forms water-clear anhedral to subhedral crystals, which are coarse to very coarse including poikilitic plagioclase, biotite and quartz. Secondary sericite is developed in it. Plagioclase forms tabular, short-prismatic and prismatic euhedral crystals and most often is included in potassium feldspar. It is zonal, and muddy due to cryptocrystalline clay minerals. Weak alteration by hydromicas, sericite and epidote is also observed. Biotite is brown, small- to middle-flaky. Epidote, chlorite and hydromicas are developed in it at places. Most often it is included in potassium feldspar. The quartz is water-clear with undulatory extinction. Accessory minerals: ore mineral forms scarce irregular crystals and aggregates and most often is included in the potassium feldspar. Small-sized rhomboid titanite crystals are also present in the rock as well as acicular euhedral zircon and short-prismatic apatite. The investigated granite has undergone a weak hydrothermal alteration.

Discussion The terrain observations, petrographical study and regional

geological setting show that the fragments of massive antique building uncovered during archaeological excavation in the village of Porominovo are made of various in age and origin, more or less hydrothermally altered granites from the West Rhodopian Block. Granites of the Late Cretaceous phases are most abundant but South Bulgarian granites of Paleozoic age are also present. The age is taken from the Geological map of Bulgaria at 1:100000 scale, Blagoevgrad map sheet (Marinova, 1991), but a more precise dating is needed. These granites have taken part in all tectonic events during the collision of the West Rhodopian Block with the Vlahina Block and the formation of Blagoevgrad graben. They are jointed, fractured, cataclased and strongly grussed. Moreover, the Late Cretaceous and probably the Paleogene magmatic and hydrothermal events were altered them and made their mechanical properties worse: they have lost the massive texture and have become jointed, fractured, and cataclased. Today these materials crop out as strongly weathered granites and coarse-grained gruss of rusty red colour. These observations exclude the possibility the stone elements of the Sabazios temple to have been obtained from quarries. Besides this, if such a quarry was present, the fragments would be unvaried, while in this case a great diversity of granites was observed.

The great diversity of granites and their high solidity suggest

that the Sabazios temple was built with stones collected from the earth’s surface and coming from the fluvial-glacial deposits in the region. It is suggested that during transport in the Ice

Age (Holocene) and rolling in river water the stone clasts with defects have been destroyed and only blocks (boulders) of high solidity without defects have left. They were widespread along the valley of the Rilska River (erratic boulders) and were used for making of columns, bases and other elements of the Sabazios temple. The case of the castle wall of Ancient Pautalia seems similar – massive plinth of solid granite blocks (Ruseva-Slokoska, 1989). The deposit of this granite is 15 km along straight line and at about 45 km on steep mountain roads. Osogovo granite has been prospected as a rock-facing material by the geological team of Lyuben Nedjin in 1978 (National Geofund) and was classified as unsuitable for industrial purpose due to fracturing and grussing up to 60 m depth.

The finding of travertine may result from sinter deposition,

consequent destruction and re-deposition in alluvial deposits. It is known that travertine was used for facades of temples and Universities due to its good sound and heat isolation properties. Carbonate rocks and mineral springs in the region as possible source of travertine are lacking. That is why it is likely, that the found piece of travertine comes from the facade of the Sabazios temple. Having in mind the small mechanical solidity of travertine it is supposed that the Sabazios temple is in close vicinity to the archaeological excavation site in the village of Porominovo.

Conclusion The stone artefacts from the Sabazios temple in the village of

Porominovo are made of granites from fluvial-glacial sediments (boulders) in the vicinity of the village and there are no evidence for prospecting of ancient granite quarries. The presence of travertine piece in the archaeological excavation is an indicator of the close location of the Sabazios temple to the village of Porominovo. Acknowledgements. The authors wish to thank Dr. I. Marinova (Central Laboratory of Mineralogy and Crystallography “Acad. Ivan Kostov”, Bulgarian Academy of Sciences) for comments on the text.

References Gerov, B. 1961. Studies on the West Thracian lands in the

Roman period. Parts 1-4. – Ann. Uni. Sofia, Phys. Fac., 54, 3, 153-407 (in Bulgarian).

Marinova, R. 1991. Geological Map of Bulgaria. 1:100000 Scale, Blagoevgrad Map Sheet. Committee of Geology, Sofia, 68 p. (in Bulgarian).

Nedjin, L. 1978. Report on the results from prospecting for decorative porphyric granite in the vicinity of the village of Novo Selo, Kyustendil District carried out in 1976-1978. National Geofund, Sofia, N II-982 (in Bulgarian).

Ruseva-Slokoska, L. 1989. Pautalia. Vol. 1 (Topography, City Structure and Fortification System). Bulgarian Academy of Science, Sofia, 152 p. (in Bulgarian)

Staikova, L. 2006. Excavation in the village of Porominovo, Kocherinovo municipality. – Museum Newspaper, Regional Historical Museum, Kyustendil, 9, 6 (in Bulgarian).