  Direct observations of the supposedly universal primordial deuterium
abundance imply a relatively large baryon density $\Omega_B=
(0.019-0.030)h^{-2}$ (95% C.L.). On the other hand, concordance between the
previously accepted $^4 He$ and $^7 Li$ abundances and standard Big Bang
Nucleosynthesis requires the thrice smaller value
$\Omega_B=(0.005-0.010)h^{-2}$ (95% C.L.). For each $\Omega_B$, we use X-ray
and Sunyaev-Zeldovich observations of the baryon fraction $f_B$ in rich
clusters of galaxies, in order to obtain limits on the total mass density
$\Omega_{cl}$ in clusters of galaxies. The higher-$\Omega_B$ values are
consistent with clusters being a fair sample of the Universe, and then imply
$\Omega_{m} =(0.3-0.9)$, a medium or critical density Universe. Said otherwise,
the observed limits $f_B > 0.1, ~ \Omega_m > 0.3$ imply $\Omega_B > 0.03$. If
the newer$^4 He$ abundance observations are accepted, this is consistent with
standard BBN.
