I really doubt they'd be consumable considering that some of them are going to be from events only (The Blazikenite presumably being the first of many).
In any case, I'm guessing they'll be obtainable in all the places you'd find typical hold items; on the ground in random places, as gifts from NPCs, and possibly as rewards to be bought with points obtained from the inevitable battle attraction.
In any case, I'm guessing they'll be obtainable in all the places you'd find typical hold items; on the ground in random places, as gifts from NPCs, and possibly as rewards to be bought with points obtained from the inevitable battle attraction.