A gas chromatographic study of the residual contents of a medieval sphero-conical vessel

Black deposit was discovered on the inner wall of a sphero-conical vessel found during archaeological excavations on the territory of the Volga Bulgars. Compounds from the deposit were extracted with organic solvents and studied by gas chromatography with flame ionization and mass spectrometry detectors. Abietic acid derivatives, including retene, present in the composition of soft wood turpentine were identified. The relatively high retene concentration in the remains of the spherocone and also the presence of other polycyclic aromatic hydrocarbons suggest the thermal version of their origin. Probably, the vessel was used as a part of alambik, which is an ancient distillation apparatus for the distillation of soft wood turpentine.