The sample referred to as "form I" shows no evidence of form II peaks in the XRPD, "low purity form II" shows form II peaks of intermediate intensity, and "high purity form II" shows the most intense form II peaks (Figure ). Here, "purity" refers to the polymorphic composition. Hence, the form I sample straightforwardly represents the aspirin form I structure, the high purity form II sample is the best available representative of the form II structure, and the low purity form II sample comprises the form II structure with a more substantial fraction of form I domains.