Identification of the Residue in the Bolgar Medieval Sphero‐Conical Vessel by Gas Chromatography – Mass Spectrometry

Abstract

The Golden Horde sphero‐conical vessel retrieved from the ruins of the medieval city of Bolgar (Russia, Republic of Tatarstan) during archaeological excavations, which contained residue in the form of encrustation on the bottom and the wall, was analysed in the NRC ‘Kurchatov Institute’ by X‐ray phase analysis and high‐performance liquid and gas chromatography with MS detectors (HPLC–MS, GC–MS). The GC–MS method established that the residue from the sphero‐conical vessel was comprised primarily of abietic acid derivatives (around 46%) and retene, which is polycyclic aromatic hydrocarbon (around 27%); this means that turpentine exuded from the stems of certain species of coniferous trees, called resin and subsequently heat‐treated, was poured into the vessel. Researchers have been trying to decipher the function of these mysterious vessels for 200 years, and this is the first time that resin stored in a sphero‐conical vessel has been documented. Potentially, this vessel was probably used as a personal ‘medical kit’.

Composition of trace residues from the contents of 11th–12th century sphero-conical vessels from Jerusalem

“…The composition of the active ingredients of some of the earliest thermal weapons include fats, oils, pitch, petroleum, asphalt, bitumen and tar [ 46 , 47 ]. The results of the molecular analysis are consistent with a container for oils, scented substances (scented oil or perfumes) or medicines as reported by Barnard et al [ 21 , 27 ] or a fuel source for a weapon, lamp, or alchemical vessel [ 45 , 50 ]. It may have multiple uses storing various chemicals or mixtures.…”

“…Overall, the presence in the residue of major components of plant oils, specifically, oleic acid and plamitoleic acid and aromatic compounds strengthens the indication of a vessel used for scented or medicinal products [ 27 ]. The GC-MS analysis of sherd 742 is similar to those results obtained by Barnard et al [ 27 ] and Pozhidaev et al [ 21 ] which were interpreted to be a scented product and medicinal product, respectively. However, the extract from sherd 742 also included a high level of sulphur and mercury, which can be found in medicinal materials, so the original vessel was a container for coloured, scented or more likely medicinal material, possibly sealed with conifer resin.…”

“…The fatty acids described above include a variety of aromatic compounds from plant sources known to provide oily, woody, floral, waxy, cheesy and pine like scent. Plant oils and resins can be flammable, aromatic or bioactive and thus can be found in the archaeological residues of incense [ 35 ], scented materials (scented oils, perfume or scented water) [ 27 ] and medicinal products [ 21 , 27 ]. Glycerol is a common solvent used for scented and medicinal products.…”

“…However, the most common function proposed for sphero-conical vessels is a container. Suggested vessel contents include liquids for human consumption including wine, honey [ 9 ], beer [ 5 ] and medicines [ 9 , 13 , 21 ]. Alternatively, valuable liquids have also been proposed like mercury [ 9 , 22 ], oil [ 6 ], rosewater [ 7 , 23 ], scented oil [ 6 ], holy water [ 9 ], ink [ 1 ], scented water [ 24 ] and perfume [ 9 , 25 ].…”

“…A study by Brosh [ 10 ] on the contents of sphero-conical vessels of unknown provenance, identified iron and proposed this was from iron pyrite which could have served as a fire starter. A study on a sphero-conical vessel from Bolgar, Russia, identified resin acids, initially interpreted as part of distillation apparatus [ 18 ], later reinterpreted as a medicinal kit [ 21 ]. Finally, fats and oils were characterised on sphero-conical vessels from Armenia that were proposed to be perfume or medicinal containers [ 27 ].…”