This dataset contains descriptions and analytical data (i.e., electron microprobe, X-ray diffraction, spectral reflectance, and scanning electron microprobe analyses) for 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. Tables of electron microprobe and spectral absorption information are also included along with ascii listings of spectral reflectance for each sample. Some of these samples, particularly the ones from Libby, Montana contain bundles of elongate amphibole capable of causing asbestosis, lung cancer, and mesothelioma.