This folder contains descriptions and analytical data (i.e., electron microprobe, X-ray diffraction, spectral reflectance, and scanning electron microprobe analyses) for unexpanded and expanded vermiculite samples. These data are provided for 52 samples of vermiculite attic insulation, horticultural products, aggregate, and packing materials derived from mines near Enoree, South Carolina; Libby, Montana; Louisa, Virginia; Palabora, South Africa; and Jiangsu, China collected from 2000 to 2016. X-ray diffraction data for a limited set of the 52 expanded vermiculite samples are also given in figures included in the sample description pdf files. Quantitative XRD diffractograms are included for an ore sample from each of the four major historical vermiculite sources. Scanning Electron micrographs of the expanded vermiculite samples or their sink fractions are also presented in the sample description pdf files. Provenance diagrams based on electron probe microanalysis and reflectance spectroscopy are provided for each of the 52 expanded vermiculite samples. Some of these samples, particularly the ones from Libby, Montana contain bundles of elongate amphibole capable of causing asbestosis, lung cancer, and mesothelioma.