In Pokémon Shining Diamond and Shining Pearl, you will try to find Flint Stones to give to specific Pokémon. They need a Firestone to achieve particular evolutions, allowing you to receive some of your favorite Pokémon and finish your PokéDex. In this guide, we will share with you where you can find the Fire Stones in Pokémon Brilliant Diamond and Brilliant Pearl.
Your best location to find Fire Stones is in the Grand Underground area. First, you'll need to get the Explorer's Kit from the old man near the Echo City Pokémo Center. It gives you the item and you can use it wherever you are, as long as you are outside.
Once you are in the Grand Underground, you need to investigate the orange icons on the side of the walls. These are fossil excavation sites, and you can unearth various valuables if you're lucky. Fire stones are among some of the evolutionary items you can find by completing this minigame. You can increase your chances of finding better items by finding Diglett and Dugtrio in the cave.
You can also receive a Firestone if you own a Pokémon with the Collect Ability. They have a chance to grab one while you hang around at your party. You can also purchase them from the Battle Tower at the end of the game using Battle Points.