Size distribution measurements of Indian tremolite asbestos by scanning electron microscopy. This material was characterized by the University of Maryland in collaboration with the US Bureau of Mines as part of studies on the nature of asbestos. The sample was provided to the University of Maryland by the US Bureau of Mines. The tremolite sample is from Rajasthan state, India. Sample obtained and measured ca. 1980. Data values were obtained with Scanning Electron Microscopy (SEM) with Energy-Dispersive X-Ray Analysis (EDXA) capability. See documentation file for full study abstract, an explanation of the content of the data files, and references to associated publications. The csv versions contain the same data as the corresponding xlsx files. The csv files are provided as a software-independent alternative to the xlsx format.