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Low resolution spectra have been used to measure individual metal abundancesof RR Lyrae stars in NGC 6441, a Galactic globular cluster known to have veryunusual horizontal branch morphology and periods of the RR Lyrae stars for itshigh metallicity. We find an average metal abundance of [Fe/H]=-0.69 +/- 0.06(r.m.s.=0.33 dex) and [Fe/H]=-0.41 +/- 0.06 (r.m.s.=0.36 dex) on Zinn & Westand Carretta & Gratton metallicity scales, respectively, consistent with thecluster metal abundance derived by Armandroff & Zinn. Most of the metallicitieswere extrapolated from calibration relations defined for [Fe/H] < -1; however,they are clearly high and contrast with the rather long periods of the NGC 6441variables, thus confirming that the cluster does not fit in the generalOosterhoff classification scheme. The r.m.s. scatter of the average is largerthan observational errors (0.15-0.16 dex) possibly indicating some spread inmetallicity. However, even the metal poor variables, if confirmed to be clustermembers, are still more metal rich than those commonly found in the Oosterhofftype II globular clusters.Comment: Accepted for publication on ApJ Letter

Metal Abundances of RR Lyrae Stars in the Metal-rich Globular Cluster NGC 6441