  A thulium-doped crystal is experimentally shown to be an excellent candidate
for broadband quantum storage in a solid-state medium. For the first time,
nuclear spin coherence is optically excited, detected and characterized in such
a crystal. The lifetime of the spin coherence -- the potential storage entity
-- is measured by means of Raman echo to be about 300 $\mu$s over a wide range
of ground state splittings. This flexibility, attractive for broadband
operation, and well fitted to existing quantum sources, results from the simple
hyperfine structure, contrasting with Pr- and Eu- doped crystals.
