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We have synthesized and crystallized a cytosine-decavanadate compound, Na(3) [V(10)O(28)] (C(4)N(3)OH(5))(3)(C(4)N(3)OH(6))(3).10H(2)O, and its crystal structure has been determined from a single-crystal X-ray diffraction. A high resolution X-ray diffraction experiment at 210 K (in P1 space group phase) was carried out. The data were refined using a pseudo-atom multipole model to get the electron density and the electrostatic properties of the decavanadate-cytosine complex. Static deformation density maps and Atoms in Molecules (AIM) topological analysis were used for this purpose. To get insight into the reactivity of the decavanadate anion, we have determined the atomic net charges and the molecular electrostatic potential. Special attention was paid to the hydrogen bonding occurring in the solid state between the decavanadate anion and its environment. The comparison of the experimental electronic characteristics of the decavanadate anions to those found in literature reveals that this anion is a rigid entity conserving its intrinsic properties. This is of particular importance for the future investigations of the biological activities of the decavanadate anion.

The prehistoric site of Vinča, on the right bank of the River Danube, the territory of the City of Belgrade, first excavated by M. Vasić in 1931–34, provides Neolithic pottery dating back to 5200–4200 BC. Shards excavated in 1998 (Serbian Academy of Sciences and Arts) have a yellow coating on the external (convex) and red deposit on the internal (concave) side. Raman, IR and x‐ray identification proved that the yellow‐to‐red decor deposited on the external faces of pottery is made of ochre, a mixture of hematite, quartz and phyllosilicates. The red deposit found on some internal surfaces of the pottery consists of cinnabar (HgS) with some quartz and phyllosilicates. This indicates that cinnabar was not used for decor but for other purposes than and prepared or stored in ceramic utensils. A comparison is made with mercury ore from the Šuplja Stena mine located ∼20 km from Vinča village. Copyright © 2004 John Wiley & Sons, Ltd.