This article examines the introduction of two technologies, photography and paper currency, in Siam (Thailand after 1939) during the early twentieth century and their roles in shaping the development of the modern Thai political economy. It does so through a historical study of a counterfeit crisis that plagued the kingdom immediately after the introduction of paper money in 1902. By analyzing the crisis, it shows how the formation of class and development of capitalism both depended on technologically reproduced symbols of the state and social status. As such, policing the distinction between genuine and fake became critical to both the identity of the new bourgeoisie and the operation of the new economy. The resulting fixation on authenticity, in turn, reflects the underlying anxiety on the part of the new elite over the basis of their authority and wealth in a rapidly changing society.