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We report for the first time rotationally resolved spectroscopic observations, as well as new photometric and polarimetric measurements, of the large S--type asteroid (6) Hebe, always at near--equatorial aspects. We have found evidence for only minor variations in Hebe's visible reflectance spectrum over a rotational cycle, comparable to our measurement accuracy (a few percent) and consistent with an undifferentiated silicate assemblage on the surface. We have also confirmed previous results of the existence of small polarization changes, but they are not correlated with the (complex and asymmetric) photometric lightcurve of the asteroid. A plausible interpretation of these data is that Hebe's surface is is composed of undifferentiated materials, but presents texture, albedo and spectral changes possibly related to the occurence of energetic cratering events. Given the comparatively large size of Hebe, its proximity to resonance--related chaotic zones of the orbital element space (Farinella et al. 1993, {\it Celest. Mech.} {\bf 56}, 287--305 and {\it Icarus} {\bf 101}, 174--187), and its assignment by Gaffey et al. (1994, {\it Icarus} {\bf 106}, 573--602) to the S(IV) taxonomic subclass, our results support the idea that this asteroid may be the source of a significant fraction of the ordinary chondrite meteorites.