- Sold by the Shrine Handmaid for 10 souls each.
- ×10 can be found in the Farron Keep, looted from a corpse near the first brazier in the poison swamp.
When used, the player will drop one of these pebbles on the ground and it will begin to sparkle in various colors, serving as a sort of marker.
They can also be dropped from ledges in order to judge whether the player will survive a fall or not. If the stone emits a shattering crystal sound, then the drop is fatal.
In online play, Prism Stones can be useful as a White Phantom to guide hosts through levels, by signaling areas and items of interest (such as treasure chests and levers) or to provide trace amounts of light without equipping a Torch.