Can aluminium form blue-colored solution in liquid ammonia?
The SE answers quoted in the comments provide a good broad answer but with respect to the question of aluminium – aluminium will form a blue solution in liquid ammonia following electrolytic reduction of $\ce{AlI3}$ in liquid ammonia according to J. Am. Chem. Soc. 1950, 72 (11), 5178–5180.
Europium and ytterbium have also been reported to dissolve in liquid ammonia in J. Phys. Chem. 1956, 60 (11), 1590–1591.