  d.c. magnetization measurements performed on a polycrystalline sample of
RuSr2GdCu2O8 (Ru-1212) showed distinct peaks of the magnetization upon entering
the superconducting state. Since Sr2GdRuO6 (Sr-2116) is the precursor for the
preparation of Ru-1212, a detailed investigation of the magnetic properties of
Sr-2116 was carried out. Although similarities were observed in the magnetic
behavior of Sr-2116 and Ru-1212 in the temperature range of the observed peaks,
we can exclude, based on a quantitative comparison, that the anomalies observed
for Ru-1212 are due to Sr-2116 impurities.
