Where To Find The Ruby

The Ruby is an item that is needed within Pokemon FireRed in order to fix Celio's Machine on One Island during the Post Game Story. This machine will allow players to ultimately Trade with those playing Pokemon Emerald via the Wireless Adapter, but it will require a player to find both the Ruby and Sapphire before being able to do so.

Out of the two crystals, the Ruby is much easier to obtain than the Sapphire. The Ruby is actually located within Mt. Ember on the northern portion of One Island, but, again, it cannot be found until you have defeat the Main Story. There's actually an entrance to go within Mt. Ember that will easily be noticeable since two Team Rocket Grunts will be blocking it. After defeating them, you will be able to access. Once inside Mt. Ember, you will have to solve a few Strength Boulder Puzzles in order to go deeper and deeper in the cave. Eventually, you will find the Ruby sitting in a room all by itself.

Once the Ruby has successfully been obtained, return it to Celio to within the One Island Pokemon Center. From there, you will be tasked with finding the much more elusive Sapphire.