A thermal emission spectral library of rock-forming minerals

A library of thermal infrared spectra of silicate, carbonate, sulfate, phos phate, halide, and oxide minerals has been prepared for comparison to spect ra obtained from planetary and Earth-orbiting spacecraft, airborne instrume nts, and laboratory measurements. The emphasis in developing this library h as been to obtain pure samples of specific minerals. All samples were hand processed and analyzed for composition and purity. The majority are 710-100 0 mu m particle size fractions, chosen to minimize particle size effects. S pectral acquisition follows a method described previously, and emissivity i s determined to within 2% in most cases. Each mineral spectrum is accompani ed by descriptive information in database form including compositional info rmation, sample quality, and a comments field to describe special circumsta nces and unique conditions. More than 150 samples were selected to include the common rock-forming minerals with an emphasis on igneous and sedimentar y minerals. This library is available in digital form and will be expanded as new, well-characterized samples are acquired.