Mid-infrared spectra (blue) of representative (a) plagioclase, (b) pyroxene, (c) olivine, and (d) glass grains, which correspond to ROI Nos. 1, 24, 6, and 16 in Table A1. The position of the Christiansen Feature (CF) is indicated by the orange dashed line, and the peaks in the Reststrahlen Band (RB) are shown by green arrows. In panel (a), the CF occurs at 8.08 μm, and two RB peaks appear at 8.95 and 10.80 μm, indicating the presence of plagioclase. In panel (b), the CF occurs at 8.59 μm, and a major RB peak appears at 9.17 μm, indicating the presence of pyroxene. In panel (c), the CF occurs at 9.15 μm, and four RB peaks appear at 9.73, 10.37, 10.86, and 12.03 μm, indicating the presence of olivine. In panel (d), the CF occurs at 8.19 μm, and a large, wide RB peak appears at 10.88 μm, indicating the presence of glass.