Can Mira Variables Tell us the Chemical Abundances in Stellar Systems?

A period-metallicity relation for oxygen-rich Miras derived from globular clusters is applied to similar variables in the galactic Bulge. The metallicity distribution in the Bulge thus obtained is in good agreement with that derived from K giants. This suggests that the periods of Miras are useful indicators of metallicity distributions, at least in old systems such as galactic bulges. For systems such as the LMC the situation is not yet clear.