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The Precambrian metamorphic suite of the Pelagonides hosts pegmatite veins in the area south of Prilep, Macedonia. A pegmatite body outcropping near the village of Dunje is notable for euhedral epidote crystals, titanite, large plagioclase crystals, amphibole and zeolite. The pegmatite intrudes gneiss of the host suite but its contact to the country rocks is not exposed well. The boundary zone becomes more prominent in the pegmatite top section. Pegmatite veinlets, a few centimeters to a decimeter in width, occur in vicinity of the larger pegmatite body and are mainly composed of quartz, feldspar and muscovite. A distinguishing local feature is occurrence of epidote not only in the Dunje pegmatite but also in the rocks of the metamorphic suite as well as in the nearby granite intrusion. Along epidote, the well-foliated host gneiss also contains amphibole, plagioclase, quartz and titanite. In the upper contact zone to the pegmatite it is less foliated and more enriched in epidote. The adjacent granite body outcrops with a typical spherical exfoliation and a mineral composition comprising abundant quartz, orthoclase (occasionally perthitic) and biotite mica. Smaller elongated or irregular grains of epidote are also observed together with titanite. The omnipresence of epidote in the Dunje complex imposes questions on genetic relations between the pegmatite and the surrounding rocks. Scanning electron microscopy with energy dispersive spectrometer (SEM-EDS) indicated a slight inhomogeneity in epidote grains in all the rocks of the complex. A single euhedral crystal of epidote about 1, 5 cm in length and recovered from the pegmatite, was cut in three sections perpendicularly to the elongation axis and prepared for the SEM-EDS analysis. The chemical data on major constituents indicate that the crystal is fairly homogeneous both along the elongation axis and perpendicular to it. The only peculiarity is a slight substitution of Mg in the middle section of the crystal and towards one end of the crystal. Preliminary chemical analysis also shows an increase of Fe content in epidote from the pegmatite and especially from the granite relative to epidote from the host gneiss. Epidote from the epidote rich gneiss in the contact zone has a higher Fe/Al ratio compared to the epidote from typical host gneiss in the area, yet this is less pronounced than in the granite and pegmatite. The sequence of epidote Fe/Al ratio variation in the rocks of the Dunje complex suggests a relation of metamorphic host and thereof potentially evolved granite and pegmatite melts. More significant iron enrichment in the granite epidote might be a result of differences in iron partitioning between epidote and biotite mica vs. epidote and amphibole in the pegmatite, however, constrained by P-T conditions and fO2 in both systems (Chang & Andronicos, 2009). A thorough chemical and textural analysis is in progress to establish more accurate genetic relations between epidote occurrences in the rocks of the Dunje complex. [1] Chang, J. M. & Andronicos, C. L. (2009): Constraints on the depth of generation and emplacement of a magmatic epidote-bearing quartz diorite pluton in the Coast Plutonic Complex, British Columbia. Terra Nova, 21, 480–488

Selečka Mountain was thoroughly investigated in the past mostly because of the interesting mineral paragenesis presented in granites, gneisses, amphibolites, different schists and pegmatite bodies. In the valley Smilevski Dol, around 3 km SW from the village of Dunje (Mariovo plateau), in the vicinity of small spring Šohlehov Kladenec hydrothermal pegmatite vein was found containing well-formed crystals of albite, microcline, amphibole, epidote, titanite, quartz, muscovite, chlorite, stilbite, heulandite, pyrite, apatite and rutile. Recent investigations brought out some more information about morphological and chemical characteristics of feldspars, namely albite and microcline and their oriented growth and confirmed garnet as new mineral in the paragenesis.

The results of new mineralogical study by the X-ray diffractions and the results of the analysis of the trace elements and rare earth elements (REE) in the ore mineralization of Crven Dol by the ICP-MS are presented in this paper. Mineralogical study suggested very interesting mineral associations presented by lorandite, realgar, orpiment, vrbaite, bernardite, jankovichite, fangite, rosenite, farmacolite, marcasite, pyrite, sulfur, gypsum, dorallcharite, dolomite, quartz. The content of trace elements and REE in the surrounding rocks and in the ore mineralization suggested the idea of influence of the ultramafic rocks from the western flank of the Vardar zone in the hydrothermal activity in the Alšar deposit, especialy in the ore body Crven Dol.

Epidote group minerals occur in various geological settings reflecting local lithology and geological history. From petrogenetic point of view these minerals are quite unspecific because of wide temperature and pressure stability fields (Franz & Liebscher, 2004). The Dunje area is situated in the Pelagonian Massif of southern Macedonia comprising a Precambrian metamorphic suite composed of gneisses, amphibolites and schists. Granitic intrusions and concomitant pegmatitic veins in the metamorphic host rocks are quite common (Temovski, 2016). The studied area is located 3 km in SSW direction from village of Dunje. Occurrence of the clinozoisite-epidote series minerals in the granitic intrusions and host gneisses in contact with pegmatite veins is investigated in this study. The studied granitic rocks outcrop roughly 100 m in NNE direction from the investigated gneiss-pegmatite contact. Plane-polarized light microscopy (Zeiss, Axiolab) and scanning electron microscopy (SEM) with EDS system (Bruker, Quantax 70) were used to study micro-features of the rock samples with special interest into the co-existence of clinozoisite-epidote minerals and Ti-rich phases, which both seem to be quite abundant in the investigated rock suite. The host gneiss is coarsely foliated and composed of clinozoisite-epidote, amphibole, quartz, plagioclase, titanite and sparse but large grains of opaque minerals. The intruding granite is composed of quartz, orthoclase with occasional perthitic lamellae, biotite, small elongated or irregular grains of clinozoisite-epidote, 533 titanite, and sparse garnet. The occurrence of clinozoisite and epidote in both host gneiss and granite represents a mineral chemistry change at small scale, and even in polarizing light epidote and clinozoisite are readily distinguished by a clear distinction in interference color. Both minerals appear mutually in a very close contact (Figure 1A and 1B ; Ep – epidote, Czo – clinozoisite, Amp – amphibole, Ttn – titanite, Pl – plagioclase). SEM-EDS analysis (Figure 1C and 1D) indicates an inhomogeneous distribution of iron throughout the clinozoisite-epidote grains, thus giving rise to a simultaneous occurrence of both phases. Amphibole is of Mg-Fe series containing some Ca (intergrowths?), and a frequent occurrence of titanite indicates a significant availability of titanium in both metamorphic suite and granite. Besides, in the host gneiss rutile grains are also identified. A detailed micro-chemical characterization of the mineral phases in the rocks of the studied metamorphic suite is in progress especially focusing to a possible relationship between occurrence of clinozoisite-epidote minerals in host rocks and granitic/pegmatitic intrusions.

According to spatial Distribution of Radon Concentration based on geological parameters and multiple linear regression method in schools of Sjenica community, Western Serbia (Balkan area)is possible to predict indoor Rn using the geological data to an acceptable level of accuracy with a limited number of measurements.

Radon variations between municipalities were significant at 95% confidence level. According to measured concentrations, the municipalities were grouped into two groups. The variation due to lithostratigraphy was also significant, but the groups were not formed. These result indicates that the influence of geology in the investigated region is uniform and that variations are relate to the buildings characteristics. The significance of the basement factor confirms the relation between indoor radon and geogenic radon potential. The radon concentrations in stone buildings are higher than those made of bricks. Considering that this factor has the highest contribution in radon variations we assume that stone despite geogenic radon is the additional source of indoor radon. Although expected, but in our case, type of windows does not affect the variations of radon, as well as type of room, altitude and the total number of floors.

The Alšar deposit consists of several ore bodies and numerous occurrences, each characterized by specific associations of metal and mineral assemblages. The antimony-arsenic-thallium-gold mineralization occurs within a zone almost 3 km long and 200 – 300 m wide. Sb and gold dominate the central part of the deposit, but it also contains significant amounts of arsenic, thallium, minor barium, mercury and traces of lead. The ore bodies contain 2 to 3% antimony, 2% arsenic, up to 0.4% thallium, up to 3.5 ppm gold and 435 ppm barium. In this paper geochemical and mineralogical characteristics of the central part of the Alšar deposit are presented along with the results of new investigations of some specimens from this area.

M20 M21

Allchar and surrounding area is well-known as polymetallic ore deposit with elevated concentrations of As, Tl, and Sb. Such ore deposit has unique impact to environment in sense of elevated heavy metals concentration in waters, soils and air. Constant influence of these toxic elements enhanced with weathering process(es) of the outcrops containing rare sulfide minerals produce environment with endemic species, like Violica Allcharica (Boev & al., 2014). Due to fact that Allchar area is distant from intensive anthropogenic influence, it represents an unique geochemical environment, but it was not studied yet for describing the geomicrobiological conditions. This study tries to identify specific interaction between mineral and living world.

LOREX, the acronym of LORandite EXperiment, is the only long-time solar neutrino experiment still actively pursued. It addresses the long-time detection of the solar neutrino flux with the thallium-bearing mineral lorandite, TlAsS2 at the mine of Allchar, FYRMacedonia, via the neutrino-capture reaction 205Tl+νe→205Pb+e−. The final step of LOREX would be the extraction of lorandite samples and the quantitative determination of the ratio of 205Pb/205Tl atoms providing the product of solar neutrino flux and neutrino-capture cross-section, integrated over the age of lorandite (about 4.3×106 y). There is an unprecedented low threshold of only 50 keV for solar pp-neutrinos, to be compared with 232 keV of the GALLEX and SAGE experiments. Moreover, LOREX would be unique in view of providing the mean luminosity of the sun over the last 4.3 million years. This paper presents new data providing an accurate geological age of mineralization at Allchar, and in particular a lower limit of 36 m/106 y for the erosion rate, based on Accelerator Mass Spectrometry of 26Al and 53Mn samples taken from the mine of Allchar. This data allow first realistic conclusions on the feasibility of the LOREX project. The amount of 205Pb due to fast cosmic rays (e.g. muons), strongly depends on the depth at which the mineral existed from the time of its formation to the present day. For the mineral mined at the present-day depth this contribution then depends upon the average erosion rate at this particular location. A reliable determination of the erosion rate is, therefore, indispensable for a proper estimate of the background of 205Pb induced by cosmic radiation. Provided that this lower limit of 36 m/106 y can be corroborated by the mandatory measurement of additional probes, it is expected to reach a signal-to-background ratio equal or better than one. Finally, it is discussed how to get the still unknown capture probability of solar pp-neutrinos from 205Tl into 205Pb, in particular into its first excited state at E*=2.3 keV.

A b s t r a c t: For determination of some hydrochemical data in the ground waters of the Bitola part of the Pelagonia valley, are taken single samples from 19 wells. Specified values for pH indicate that the waters belong to the group of slightly alkaline ground water (pH = 7.2 – 8.9). Following to the classification of Alekin the majority of tested water according the content of the anion fall into hydrocarbonate class, calcite group and a smaller number in the chloride and sulfate class, sodium and magnesium group. Increased values of TDS, Ca2+, Mg2+, Na+, K+, HCO3 -, Cl– and NH4 + occurs in the ground water from deeper artesian and subartesian wells, as a result of the longer retention time of water in the underground and its interaction with the geological environment. Ground water from the shallow wells occurs the increasing content of PO4 3– and NO3 – which indicates water pollution from fertilization of the cultivated areas, livestock farms as well as communal waste water. Knowing the hydrochemical feature of the ground water from the research area is from particular importance, because the water from these wells 5s used by the inhabitants of the region as industrial water, water for irrigation, packaging of mineral water and the exploitation of CO2.