Fairy Stone

An old miner's song suggests these are made from the bones of ancient fairies.
Overview
Fairy Stone is a mineral that can be found in the 

Its main gameplay use is in tailoring and dyeing. When placed in the spool of the 


Because Fairy Stone is both a mineral and a dye source, it is worth holding onto even if it is not needed for crafting right away. Players who like customizing clothing may want to save extra copies, since it can serve a practical role in fashioning new shirts or producing purple-toned dyes. This makes it more useful than a mineral that exists only as a museum donation or sellable collectible.
In practice, Fairy Stone is most relevant to players who frequently open geodes or engage with the Sewing Machine. Opening Frozen Geodes and Omni Geodes gives it a chance to appear alongside a variety of other minerals and resources, so it is usually best treated as a flexible utility item rather than something to consume immediately. If you are collecting materials for tailoring, dyeing, or general storage, keeping at least one Fairy Stone on hand is a good idea.
Official description
An old miner's song suggests these are made from the bones of ancient fairies.