Ancient Seed

It's a dry old seed from some ancient plant. By all appearances it's long since dead...
Overview
Ancient Seed is an artifact that can be donated to the Museum, where it counts toward the total number of museum donations. The first Ancient Seed artifact the player finds has no productive use beyond that donation. When Gunther receives it, he rewards the player with one pack of plantable 
The resulting Ancient Seeds are a separate craftable item, and the recipe is learned by donating Ancient Seed to the Museum. Ancient Seed itself is not used in any bundles. It can also be placed in the spool of the 
In practice, Ancient Seed is best treated as a museum milestone item rather than something to keep for direct use. After the initial donation, additional artifacts can be converted into seeds instead of taking up storage space, which lets the player turn future finds into a crop source rather than a duplicate artifact.
Official description
It's a dry old seed from some ancient plant. By all appearances it's long since dead...