  The coexistence between the hcp and bcc phases of solid 4He at fixed
pressure, and at three different temperatures, is studied by means of the path
integral Monte Carlo method. Microscopic results for the main energetic and
structure properties of the two phases are reported. The differences between
hcp and bcc 4He are shown to be small with the obvious exception of the static
structure factor. When crossing the phase transition line, the most significant
changes are observed in the kinetic energy per particle and in the Lindemann
ratio, both pointing to a less correlated quantum solid in the bcc side. No
off-diagonal long-range order is observed in the the hcp and bcc perfect
lattices.

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