The bullet is destroyed by the impact, but the sheer kenetic
energy of the impact also damages the granite...
The macross idea sounds like Enterprise's Hull Polarization, before
the humans discovered gravitometric shielding, where a powerful EM
charge is passed through a special metal alloy to polarize it,
increasing it's mechnical strength greatly via the field currents,
and allowing it to absorb and redirect energy, lessening the damage
done to it by assualts.
Hmm cool...
