Response to comment on "Comparison of laboratory emission spectra with Mercury telescopic data" by Melissa Lane

The laboratory spectrum published in Fig. 3 of A. L. Sprague and T. L. Rous h (1998, Icarus 133, 174-183) is a mixture of magnetite and hematite (simil ar to 34-45% magnetite, similar to 55-66% hematite) rather than magnetite o r hematite (M. D. Lane 2000, Icarus 143, 000-000) alone. Because of the unu sual nature of this sample (it is uniformly magnetic) we present results of X-ray diffraction, petrographic microscopy, and additional microprobe anal yses. We compare this spectrum with laboratory spectra of hematite and magn etite. We can draw no conclusions regarding the presence or absence of magn etite on Mercury based solely on data in the spectral region 7.5-12 mu m. ( C) 2000 Academic Press.