Leather

Nothing in this list is craftable in turn, so one Leather is a single step: 1 unit of material drawn from a single base item, plus 1 crystal.

That is the lightest raw-material bill on the site, tied with 3,129 other recipes, and 9,374 recipes nest deeper.

The single raw material does not appear in the gathering data, so the whole bill comes from vendors, drops or content this site does not track.

Leather is itself consumed by 59 further recipes, spanning seven of the eight crafting classes.