In the production of things, and, more generally, in all human acts of making, materials – which possess particular properties that enable a certain range of manipulations by the human hand – undergo a series of transformations, fi rst into the ‘raw materials’ of human use by means of specialized practices and technologies, then into objects and things, and, fi nally (or, rather, concurrently), humans assign meanings to these things by integrating them into systems of knowledge and belief (or, ‘theories’). This is a reciprocal rather than linear process, and this chapter seeks to follow this complex and often partially obscured itinerary of materials, techniques, and ideas as they travel across geographic and epistemic space in Eurasia to form an ‘amalgam’ or ‘assemblage’ that I will label a ‘material complex’ .