Several attempts at autonomous interpretation of PXRD data have been made. Mayo et al. match experimental patterns of organic polymorphs to a database of calculated structures. Lunt et al extended this methodology to identify polymorphs of organic materials crystallised and analysed in a robotic lab. Salgardo et al. used machine learning to classify crystal system and space group from experimental PXRD patterns. The three aforementioned studies are important advances, and a large part of their value is in clearly outlining the limitations of the methodology. Each has a far more modest goal than unsupervised Rietveld Refinement of unknown compounds.