  Surface abundances of 14 (11 majority class and 3 minority class) R Coronae
Borealis stars (RCBs) along with the final flash object, V4334 Sgr (Sakurai's
object) are revised based on their carbon abundances measured from the observed
C2 bands; note that the earlier reported abundances were derived using an
assumed carbon abundance due to the well known ``carbon problem''. The hot RCB
MV Sgr is not subject to a carbon problem; it is remarkable to note that MV
Sgr's carbon abundance lies in the range that is measured for the majority and
minority class RCBs. The revised iron abundances for the RCBs are in the range
log E(Fe)=3.8 to log E(Fe)=5.8 with the minority class RCB V854 Cen at lower
end and the majority class RCB R CrB at the higher end of this range.
Indications are that the revised RCBs' metallicity range is roughly consistent
with the metal poor population contained within the bulge. The revised
abundances of RCBs are then compared with extreme helium stars (EHes), the
hotter relatives of RCBs. Clear differences are observed between RCBs and EHes
in their metallicity distribution, carbon abundances, and the abundance trends
observed for the key elements. These abundances are further discussed in the
light of their formation scenarios.
