  We show that coherent $\eta$ and $\etap$ photoproduction by means of the
Primakoff Effect on the proton depends on the strange component of the neutral
axial current coupling. We construct polarization asymmetries that are
sensitive to this coupling through the $\gamma - Z$ interference. The
$\eta^\prime$ is not a Goldstone boson of a spontaneously broken chiral
symmetry, but a phenomenological analysis of the $\eta$ and $\eta^\prime$
production through chiral perturbation theory allows to calculate the
observables of interest. The polarized proton or polarized photon asymmetries
are predicted to be close to
  $10^{-4}$ for $-q^2 \sim 0.1-0.5\;\mbox{\rm GeV}^2$.
