Pokémon Brilliant Diamond and Pokémon Shining Pearl offer a variety of evolutionary items like the Prism Scale that players can use to evolve a particular Pokémon. The Prism Scale, in particular, is used to evolve Feebas into Milotic.
The Prism Scale is a hard-to-get item because of the uncertainty attached to the process in which you can obtain it. In the wake of that, in this Pokémon Brilliant Diamond and Pokémon Shining Pearl guide, we share the location where you can find the Prism Scale.
Where to Find a Prism Scale
In Pokémon Brilliant Diamond and Pokémon Shining Pearl, you can find the Prism Scale evolutionary item in Fossil Sites, in Grand Underground.
You can access the Grand Underground via Eterna City. To unlock the area, you need an Explorer’s Kit. You can get it from the old man found right of Eterna City Pokémon Center
Once you enter the Grand Underground, explore the Fossil Sites denoted by orange dots on the game map. When you dig a fossil site, you have chances to obtain rare items, including the Prism Scale. Though keep in mind, the drop rate is not 100%.
Pokémon Brilliant Diamond and Shining Pearl are currently available on the Nintendo Switch platform.