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Multiple rock‐magnetic and non‐magnetic techniques were employed to identify iron sulfides in late Pleistocene Czech loess deposits. The results indicate that iron sulfides in the loess at Znojmo section are mainly pyrrhotite and pyrite, with stoichiometry ranging from Fe10S11 to FeS2. Although early pedogenic origin of fine sulfide fraction can not be ruled out, scanning electron microscopy (SEM) of individual grains and microscopic observations of magnetic extracts show that iron sulfide grains are probably of detrital origin. Potential sources of these sulfides may have been eluvium loams above hypothetical ore deposits in the vicinity of the section or glacifluvial sediments from nearby glacial margins. Framboidal pyrite forms, now completely replaced by iron oxides, suggest that some particles of biogenic sulfides may have also been transported into loess from presumably fluvial sediments.

Magnetic susceptibility, organic matter content, and grain size were measured on a loess/palaeosol sequence deposited since the last interglacial at the Dolni Vestonice section in the Czech Republic. High values in magnetic susceptibility and organic matter content in palaeosols PK0, PK2, and PK3 indicate that they were strongly influenced by long‐term pedogenesis and high vegetation density linked to interglacials or interstadials. Grain‐size variations record a series of cold wind‐strengthened events during the last glacial, which we interpret as a record of the distinctive ‘Younger Dryas’ episode and millennial‐scale climate oscillations that correlate with the GRIP ice core δ18O record and North Atlantic Heinrich events. These climate events, as indicated by grain‐size peaks, combined with previous climate records at French Massif Central and Lago Grande di Monticchio in Italy, suggest that the climate over these areas might have undergone synchronous oscillations with the shifts in sea‐surface temperatures of the North Atlantic and air temperature changes above Greenland.