  We review silicate chondrules and metal-sulfide nodules in unequilibrated
enstatite chondrites (EH3 and EL3). Their unique mineralogical assemblage, with
a wide diversity of opaque phases, nitrides, nearly FeO-free enstatite etc.
testify to exceptionally reduced conditions. While those have long been
ascribed to a condensation sequence at supersolar C/O ratios, with the
oldhamite-rich nodules among the earliest condensates, evidence for relatively
oxidized local precursors suggests that their peculiarities may have been
acquired during the chondrule-forming process itself. Silicate phases may have
been then sulfidized in an O-poor and S-rich environment; metal-sulfide nodules
in EH3 chondrites could have originated in the silicate chondrules whereas
those in EL3 may be impact products. The astrophysical setting (nebular or
planetary) where such conditions were achieved, whether by depletion in water
or enrichment in dry organics-silicate mixtures, is uncertain, but was most
likely sited inside the snow line, consistent with the Earth-like oxygen
isotopic signature of most EC silicates, with little data constraining its
epoch yet.
