Dental enamel lesions are formed by the demineralisation of dental enamel due to dietary and bacterial factors which lower the local pH. If progression of this demineralisation continues the enamel structure eventually fails giving rise to a cavity (carie). Fortunately, in the earliest stages this process is reversible and if the pH of the environment increases, ions such as calcium, phosphate and fluoride can diffuse back into the enamel to give an arrested lesion. Hence, the tooth's structural integrity is preserved. The use of artificially produced enamel caries allows the study of lesion formation under conditions of highly controlled demineralisation. This provides a fundamental insight into the process of caries formation in enamel. In this study human premolars have been treated with a lactic acid solution to create artificial “caries-like” lesions in the enamel on the buccal side of the teeth. In the test samples the lesions penetrated around 100 μm into the enamel structure, accounting for approximately one tenth of the thickness of the enamel. Cross sections through the lesion were characterized with nanoindentation, electron probe micro-analysis and time of flight secondary ion mass spectrometry. From the data obtained maps of both mechanical and chemical properties were plotted across the entire width of the lesions. The results show that the lesions have a significantly reduced hardness and elastic modulus in comparison to sound enamel. These changes in mechanical properties were found to correlate with a loss of calcium and phosphate from the structure. There was also evidence of a stronger, less demineralised layer of enamel close to the lesion's surface. This surface zone is suggestive of remineralisation within the lesion which is of importance with regards to preventing the lesion developing into a carie.