  We present medium-resolution spectra of 16 radial velocity red-giant members
of the low-luminosity Bootes I dwarf spheroidal (dSph) galaxy, that have
sufficient S/N for abundance determination, based on the strength of the Ca II
K line. Assuming [Ca/Fe] ~ +0.3, the abundance range in the sample is Delta
[Fe/H] ~ 1.7 dex, with one star having [Fe/H] = -3.4. The dispersion is
sigma([Fe/H]) = 0.45 +/- 0.08 -- similar to those of the Galaxy's more luminous
dSph systems and Omega Centauri. This suggests that the large mass (greater
than approximately 10 million solar masses) normally assumed to foster
self-enrichment and the production of chemical abundance spreads was provided
by the non-baryonic material in Bootes I.
