Salt crystallisation is a principal deterioration factor of many stone monuments. In this study, samples of weathering products of two baroque monuments in Ljubljana, Slovenia (the Fountain of Three Carniolian Rivers and the side altar of the Church of St. James), as well as the limestone used in their construction (Lesno Brdo limestone) were investigated in order to ascertain the main mineral phases produced during the weathering process. A combination of micro-Raman spectroscopy and X-ray powder diffraction was successfully applied to identify micrometre-size minor components in the limestone and the weathering product phases. In addition to calcite and dolomite as the main components of the Lesno Brdo limestone, quartz, anatase, goethite, haematite and phyllosilicates were also determined as minor limestone minerals. The limestone was found to be extensively deteriorated in both outdoor and indoor environments in the studied historical monuments, showing flaking, subflorescence, efflorescences, crumbling and black and white crusts as a result of the deterioration phenomena. Among these weathering forms, efflorescences were found to be more complex in terms of mineral assemblage, where gypsum was associated to hexahydrite, pentahydrite, and nitre. In contrast to the efflorescences, the mineralogy of subflorescences as well as that of white and black crust from outdoor and indoor conditions was rather simple, composed of only gypsum. The results showed that gypsum also crystallised under the surface as subflorescence, which eventually led to the flaking and crumbling of the limestone.

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Roman slag from the archaeological site near Mo{nje (NW Slovenia) was studied with respect to its mineralogical and geochemical characteristics. Samples were analysed with light microscopy, X-ray powder diffraction (XRD), scanning electron microscopy with an energy dispersive spectrometer (SEM-EDS) and Raman microspectroscopy. A chemical investigation was carried out using inductively coupled plasma-atomic emission spectroscopy (ICP-ES) to determine the major elements. The investigated slags are recognized as iron slags, grouped into two main classes according to their chemical and mineralogical compositions. The first group is characterized by high Fe2O3 and low SiO2 contents and the second by high CaO and SiO2 and low Fe2O3 contents. The phase occurrence obviously depends on the chemical composition as the first group mainly consists of fayalite, wüstite and magnetite, and the second one of augite, leucite, hedenbergite, monticellite and kirschsteinite. Keywords: slag, archaeometallurgy, iron slag, Roman slag, archaeological site near Mo{nje (Slovenia) V prispevku je obravnavana rimska`lindra z arheolo{kega najdi{~a Mo{nje (SZ Slovenija), pri kateri smo dolo~ili mineralno in kemijsko sestavo. Vzorci so bili analizirani s svetlobno mikroskopijo, rentgensko pra{kovno difrakcijo, SEM-EDS in ramansko mikrospektroskopijo. Kemijska sestava glavnih elementov je bila dolo~ena z ICP-ES. Preiskana`lindra dokazuje, da izvira iz pridelave`eleza na tem podro~ju. Glede na mineralo{ko in kemijsko sestavo lahko delimo`lindro na dve skupini. Za prvo skupino je zna~ilna visoka vsebnost Fe2O3 in nizka vsebnost SiO2, za drugo pa visoki vsebnosti SiO2 in CaO ter nizka vsebnost Fe2O3. Kemijska sestava vpliva na mineralne faze; tako je za prvo skupino zna~ilen fajalit, wustit in magnetit, za drugo pa avgit, levcit, hedenbergit, monticelit in kirschsteinit.

A new silicate, colinowensite, BaCuSi2O6, has been found in the Wessels mine, Kalahari Manganese Field, South Africa. It is associated with effenbergerite, wesselsite, lavinskyite, scottyite, diegogattaite, as well as with pectolite, quartz, aegirine, richterite, minerals of the garnet group and a number of different manganese and iron oxides, especially hausmannite and hematite. The mineral was named for the mineral collector and finder of the new species, Colin R. Owens, of Somerset West, South Africa. Colinowensite is brittle, with uneven fracture, and the estimated Mohs hardness is ∼4. It occurs as subhedral crystals <100 μm in size. The forms {100} and {110} are observed while {001} is always present in cleavage plates. The calculated density is 4.236 g cm–3. It is the natural analogue of the synthetic pigmentreferred to as Chinese or Han purple, which is found on artifacts from ancient and imperial China. The mineral is of dark blue to purple colour, with a purple streak, and is uniaxial (–), with ω = 1.740 (20), ε = 1.735 (20) (420 nm) and ω = 1.745 (20), ε = 1.730(20) (650 nm). The lustre is vitreous and no fluorescence is observed under either shortwave or longwave ultraviolet radiation. Avery strong pleochroism occurs from purple along the c axis to blue in a perpendicular direction. Colinowensite is not soluble in acids except HF. Electron microprobe analyses gave an average composition (wt.%) of CuO 22.53, BaO 43.43 and SiO2 34.04 yielding the empirical formula (based on 6 O a.p.f.u.) BaCuSi2O6. The new mineral is tetragonal, space group I41/acd with Z = 16, anda = 9.967(1), c = 22.290 (2) Å. Colinowensite is a cyclosilicate with [Si4O12]8– 4-membered single rings, arranged in sheets parallel to (001). The structure is further characterized by CuO4 squares sharing corners with four neighbouring silicate rings within a sheet. Ba2+ cations are bonded to ten O atoms in irregular coordination. Average Si–O, Cu–O and Ba–O bond lengths are 1.619, 1.934 and 2.943 Å, respectively. Colinowensite belongs to subdivision 9. CE of the Strunz Mineralogical Tables. In addition, based on single-crystal X-ray work, new structural data for wesselsite of chemical composition Sr0.9Ba0.1CuSi4O10 are provided.