  The abundance ratios of some chemical species have been found to correlate
with stellar age, leading to the possibility of using stellar atmospheric
abundances as stellar age indicators. These chemical clocks have been
calibrated with solar-twins, open clusters and red giants, but it remains to be
seen whether they can be effective at identifying coeval stars in a field
population that spans a broad parameter space (i.e., the promise of chemical
tagging). Since the components of wide binaries are known to be stars of common
origins, they constitute ideal laboratories for testing the usefulness of
chemical clocks for the age dating of field stars. We determined the abundances
of a new sample of 5 binaries and collected data for other 31 systems from the
literature in order to test the applicability of chemical clocks. We recover
the well known result that the components of wide binaries have more consistent
chemistry than that of random pairs. However, we also show for the first time
that abundance ratios designed as chemical clocks are even more consistent
among the components of wide binaries than their [X/Fe] ratios. Not only that,
but the special case of the pair HIP 34426/HIP 34407 may indicate that chemical
clocks are consistent for coeval stars even when the individual abundances are
not. If the assumption that chemical clocks are reliable age indicators is
correct, this would constitute first quantitative, statistically significant
evidence that the components of wide binaries in the Galactic field are indeed
coeval, validating a large body of published work that relies on that to be the
case. Moreover, our results provide strong evidence that chemical clocks indeed
carry important information about stellar birthplaces and chemical evolution,
and thus we propose that including them in chemical tagging efforts may
facilitate the identification of nowadays dissolved stellar groups.
