  We examine the composition of the 0.1 - 1 MeV/n interplanetary heavy ions
from H to Fe in corotating interaction regions (CIRs) measured by the SIT
(Suprathermal Ion Telescope) instrument. We use observations taken on board the
two STEREO spacecraft during the unusually long minimum of Solar Cycle 23 from
January 2007 through December 2010. During this period instruments on STEREO
observed more than 50 CIR events making it possible to investigate CIR ion
abundances during solar minimum conditions with unprecedentedly high
statistics. The observations reveal annual variations of relative ion
abundances in the CIRs during the 2007 - 2008 period. In 2010 the elemental
composition in CIRs were influenced by solar energetic particle events.
