  In the whole landscape of atomic nuclei, $^{229}$Th is currently the only
known nucleus which could allow for the development of a nuclear-based
frequency standard, as it possesses an isomeric state of just 7.6 eV energy
above the ground state. The 3+ charge state is of special importance in this
context, as Th$^{3+}$ allows for a simple laser-cooling scheme. Here we
emphasize the direct extraction of triply-charged $^{229}$Th from a buffer-gas
stopping cell. This finding will not only simplify any future approach of
$^{229}$Th ion cooling, but is also used for thorium-beam purification and in
this way provides a powerful tool for the direct identification of the
$^{229}$Th isomer to ground state nuclear transition.
