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A small group of opaque yellow glazed sherds has recently been identified among the ceramics excavated at the Islamic city of Madinat al-Zahra’ near Cordoba, in al-Andalus (southern Spain), which was founded in 936 AD as the seat of the Umayyad Caliphate power. A small group of sherds from Madinat al-Zahra’, which can be dated to about 960–980 AD, has been examined in polished section in a SEM with EDS attached. These analyses have established that the Madinat alZahra’ sherds were opacified with lead stannate, and not lead antimonate, as was being used to opacify yellow glazed ceramics in Egypt and Tunisia in the ninth and tenth centuries AD. Islamic opaque yellow glazed ceramics, with lead stannate as the opacifier, were first produced (Beiträge Zur Islamischen Kunst Und Archäologie 4:125–144, 2014) in Egypt and Syria in seventh/eighth centuries AD, and from there, the technology spread eastwards into Iraq and Iran in the ninth century AD and continued in use in Iran and Central Asia into the tenth century AD and beyond. However, the question of where these opaque yellow glazed ceramics were produced has not been fully resolved. Because such ceramics are extremely rare in al-Andalus, it seems most likely that they were either imported from Iran or Central Asia or produced locally by potters arriving from these areas. The study adds one further, yet not fully understood chapter to the story of a persistent glaze technology which has been widely ignored., Peer Reviewed, Postprint (author's final draft)

A small group of opaque yellow glazed sherds has recently been identified among the ceramics excavated at the Islamic city of Madinat al-Zahra’ near Cordoba, in al-Andalus (southern Spain), which was founded in 936 AD as the seat of the Umayyad Caliphate power. A small group of sherds from Madinat al-Zahra’, which can be dated to about 960–980 AD, has been examined in polished section in a SEM with EDS attached. These analyses have established that the Madinat alZahra’ sherds were opacified with lead stannate, and not lead antimonate, as was being used to opacify yellow glazed ceramics in Egypt and Tunisia in the ninth and tenth centuries AD. Islamic opaque yellow glazed ceramics, with lead stannate as the opacifier, were first produced (Beiträge Zur Islamischen Kunst Und Archäologie 4:125–144, 2014) in Egypt and Syria in seventh/eighth centuries AD, and from there, the technology spread eastwards into Iraq and Iran in the ninth century AD and continued in use in Iran and Central Asia into the tenth century AD and beyond. However, the question of where these opaque yellow glazed ceramics were produced has not been fully resolved. Because such ceramics are extremely rare in al-Andalus, it seems most likely that they were either imported from Iran or Central Asia or produced locally by potters arriving from these areas. The study adds one further, yet not fully understood chapter to the story of a persistent glaze technology which has been widely ignored., Postprint (author's final draft)

The major findings of ~20 years of research on the analysis of antimony species in environmental samples are summarised in this paper. The complex chemistry of antimonite (SbIII) as well as of antimonate (SbV) plays a major role in chromatographic speciation of these species. For simple matrices, like surface or ground-water samples, antimony redox speciation has become a routine analysis and is robust and highly reproducible, if certain aspects are taken into consideration. These aspects are the formation of a stable complex of SbIII and complex formation kinetics. Then the antimony redox species can be separated on an anion-exchange column and detected with a suitable element detector (inductively coupled plasma–mass spectrometry (ICP-MS) or hydride generation–atomic fluorescence spectrometry (HG-AFS)) for trace analysis. The influence of complexing agents in the sample matrix, or in the eluent, on the formation of SbIII and SbV complexes and possible corruption of chromatography is discussed. This ability of antimony to form rather stable complexes also increases the risk of artefact formation during extraction of solid samples.

Individual uptake of As and Sb species in Pteris vittata have been investigated, but little information is available how uptake is affected if both metalloids are simultaneously present in different amounts. We investigated the uptake of antimony and its speciation in Pteris vittata cultivated in quartz substrate with, versus without, co-contamination with arsenic and a contaminated soil for 7 weeks. Applying HPLC-ICP-MS technique Sb(V), Sb(III), As(III), and As(V) could be identified as main species in aqueous extracts of roots and fronds with up to 230 mg kg−1 of total Sb in the roots. Adding increasing amounts of As to the quartz substrate resulted in increasing uptake of Sb. In contrast to As, which is readily transferred to the fronds, Sb is primarily accumulated in the roots with Sb(V) being the dominant species (>90% of Sb). The addition of As doesn't result in enhanced translocation of Sb into the fronds.

The remobilization of antimony and vanadium from previously loaded commercial granular ferric-hydroxide GEH material (intended for water treatment) was examined by using a sequential extraction procedure and three different leaching systems to evaluate their physicochemical mobility and potential availability under different simulated environmental conditions. A classical batch extraction, an extraction cell (EC) and rotating-coiled columns (RCC) were used as extraction systems.For each system it could be shown that the content of ion-exchangeable antimony and vanadium in previously loaded material is negligible (<1.5%). The oxyanions were sorbed strongly and could be predominantly remobilized through reducing agents, which means through dissolution of the iron (hydr)oxide matrix.The major advantages of dynamic systems in comparison to batchwise fractionation technique are the drastically reduced extraction time and the possibility of generating information to the leaching kinetics. It is shown that the efficiency of the three leaching systems is quite different employing Wenzel's sequential fractionation protocol. Only by working with RCC, the iron (hydr)oxide matrix was completely dissolved within four steps resulting in the total mobilization of antimony and vanadium. EC seems to be less suitable for leaching studies of Sb and V sorbed on iron(hydr)oxide. The remobilizable proportion of the several fractions was lower in comparison to batch and RCC and seems to be a result of an agglomeration of the GEH in the EC device.

This review focuses on the vibrational spectroscopy of the compounds and minerals containing the arsenite, antimonite and antimonate anions. The review collects and correlates the published data.

Raman spectra of antimonate mineral brizziite NaSbO3 were studied and related to the structure of the mineral. Two sharp bands at 617 and 660 cm-1 are attributed to the SbO3- symmetric stretching mode. The reason for two symmetric stretching vibrations depends upon the bonding of the SbO3- units. The band at 617 cm-1 is assigned to bonding through the Sb and the 660 cm-1 to bonding through the oxygen. The low intensity band at 508 cm-1 is ascribed to the SbO antisymmetric stretching vibration. Low intensity bands were found at 503, 526 and 578 cm-1. Sharp Raman bands observed at 204, 230, 307 and 315 cm-1are assigned to OSbO bending modes. Raman spectroscopy enables a better understanding of the molecular structure of the mineral brizziite.