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Calcite crystals were grown from solution with single-crystal dimensions up to 3 mm and doped up to ~0.1 at% with Nd 3+ ions. Phase purity was verified by powder X-ray diffraction. The concentration of Nd 3+ was measured by energy-dispersive spectrometry and Rutherford backscattering spectrometry. Micro X-ray fluorescence mapping of the calcite grains indicates uniform Nd distribution in as-grown crystal grains. X-ray absorption fine structure suggests that Nd 3+ is substituted for Ca 2+ with local lattice distortion. Temperature-dependent near-infrared spectroscopy of Nd 3+ impurities in calcite reveals large inhomogeneous linewidths and smooth line profiles that are characteristic of glassy hosts, though the samples are well crystallized. [ABSTRACT FROM AUTHOR]