  We discuss the production of the element $^6$Li in the early Galaxy by cosmic
rays accelerated at structure formation shocks, driven by the hierarchical
merging of sub-Galactic halos during Galaxy formation. The salient features of
this scenario are discussed and compared with observations of $^6$Li in
metal-poor halo stars, including a recent Subaru HDS result on the star
HD140283. Some unique predictions of the model are clearly testable by future
observations and may also provide important insight into how the Galaxy formed.

Astrophysics