Early modern alchemical recipes often describe marvellous effects – the transmutation of base metals into gold and silver, or the production of elixirs capable of greatly prolonging life. Yet what were alchemists “really” making and doing? Some historians of alchemy have tried to answer this question by restaging alchemical experiments in modern laboratories: assessing whether their reading of a source is correct, by comparing experimental observations with the encoded instructions often found in alchemical recipes. However, alchemy presents particular problems for re-enactment – given that its goals are not achievable according to modern scientific understanding, how far can experimental replication take us in this field? At what point did alchemical authors cease to describe their own observations and fall back on earlier (impossible) accounts? And in a modern re-enactment, how can we tell when we have reached the same point? I will illustrate this discussion using footage of my own attempts at re-enacting sixteenth-century alchemical experiments.