In Pokemon Omega Ruby, I've been looking all over for the Charizardite X and Y, and still don't know where they are, so basically, I need to know the location for the two charizardites.
Charizardite X can be found in Fiery Path after the Primal Groudon/Kyogre narrative. Note: Strength is needed to obtain it.
Charizardite Y can be found in Scorched Slab after the Primal Groudon/Kyogre narrative.
For more help getting both Mega Stones, check out this video for the Charizardite X and this video for the Charizardite Y.