Trace element compositions of raw clay, fired clay and Roman ceramic building material (CBM) from Carpow Roman fortress, Newburgh, Scotland and the city of York, England have been determined through the use of inductively coupled plasma-mass spectrometry (ICPMS). It is confirmed that the firing of clay does not disturb any of the sample's trace element composition and that trace element protolith identification is an applicable tool for fingerprinting the source of material used in CBM construction. It is also demonstrated through the particular proportions of LREE/HREE; Th/Co; La/Sc; La/Lu; Eu/Sm values on CBM from Carpow that these material were likely manufactured from clay used in the York Roman tile manufacturing industry, therefore suggesting importation. The transport of CBM from York to Carpow provides a useful addition to known examples of the long-distance shipping of CBM. It is postulated that similar analysis to that conducted here could be used to identify important trade networks within the Roman Empire. (C) 2012 Elsevier Ltd. All rights reserved.