The third painted panel of the Hoz de Vicente rock shelter (Minglanilla, Cuenca, Spain) contains a series of prehistoric pictographs which were studied by Raman microscopy. Scanning electron microscopy (SEM), energy dispersive X-ray microanalysis (EDX) and petrographic polarised light microscopy were used as auxiliary techniques. The results obtained indicate that well-crystallised haematite (α-Fe 2 O 3 ) of grain size less than 1 µm was used as red pigment. However, amorphous carbon, probably vegetable charcoal or soot, was used as the black pigment. A patina of whewellite and weddellite covers the areas of the painting panel with pictographs. The microstratigraphic study of a schematic figure revealed that the layer of pigment is sandwiched between layers of these hydrated forms of calcium oxalate produced by the activity of fungi and lichens. These products have also been detected in the layer of pigment. These findings will enable obtaining limiting radiocarbon 14 C accelerator mass spectrometry (AMS) dates for the corresponding pictorial events. On the other hand, crystallisation of gypsum in the external layers of the panel is related to the deterioration observed in the flaking areas. Gypsum and clayish minerals appear as the main components of an ochre-coloured accretion covering several parts of the panel.

In situ micro‐Raman spectroscopy (μ‐RS) of rock art paintings in open‐air rock shelters entails several difficulties: sunlight, wind, dust and crusts that mask Raman signals from the pigments and any other component of the paint recipe. These problems have been considered in the present work. Special attention has been devoted to the presence of crusts. Five rock art sites in the eastern Iberian Peninsula with outstanding difficulties to be analysed by this technique have been the object of this study. In situ energy dispersive X‐ray fluorescence and diffuse reflectance infrared Fourier transform spectroscopy using portable instruments have provided important help. Moreover, microstratigraphic studies by μ‐RS and scanning electronic microscopy combined with energy dispersive X‐ray spectroscopy of micro‐specimens from the painting panels have revealed the distribution of the different components. Dolomite and calcite are dominant minerals in the rock substrata. Whewellite, gypsum, calcite, clay, dolomite, α‐quartz, anatase and haematite have been found on the surface of the painting panels or forming stratified layers in the crusts. Haematite and amorphous carbon have been detected in red and black pictographs, respectively. Copyright © 2014 John Wiley & Sons, Ltd.

AB5TRACTThe aim of this study is to provide the first detailed mineralogical and fluid-inc1usion description of emeralds from the Delbegetey deposit (Kazakhstan). The characteristic features of Delbegetey emeralds are established: they have dissolution figures on crystal faces, bluish colour and distinct colour zoning; the refractive indices are ro = 1.566-1.570, E = 1.558-1.562, and the specific gravity is 2.65±0.005, relatively low for natural emeralds; they have very small concentrations of the impurities (Fe, Mg, Na and others) typical of other emeralds, and contain Cr and V; there is a significant preponderance of vapour in fluid inc1usions of all types and there is liquid-to-vapour homogenization of primary fluid inc1usions (at 395-420°C). The lattice oxygen isotope composition data obtained (0 18 0 SMOW value of 11.3%0) situate the deposit within the range characteristic of other granite-related emerald deposits. Emerald crystallization took place in low-density (0.40-0.55 g/cm 3 ) aqueous fluid, with the following chemical composition (mol.%): 75.6-97.4 HzO, 0.0-18.4 caz, 0.0-0.9 C~, and 4.06-9.65 wt.% NaCI equiv. salinity. According to the calculated isochores, the pressure offormation ofthe Delbegetey emeralds can be estimated at 570-1240 bar.

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