Dwarven Cotton

Taken all the way down to base materials, one Dwarven Cotton is 2 crafting steps deep and needs 1 intermediate — Dwarven Cotton Thread ×3 — which resolves to 1 distinct raw material totalling 4 units, plus 7 crystals.

That bill outweighs 3,935 of the 13,602 recipes tracked here and 436 of the 1,968 Weaver ones, and 4,464 recipes nest deeper.

Only 4 of those crystals go into the final step; the other 3 are burned by the intermediates, so the real crystal cost is 7 Lightning Crystal.

Every step is Weaver work, from a Lv 78 intermediate up to the Lv 78 finish, so one class covers the whole chain.

Its single raw material is gathered, and no spot for it is timed, so nothing in the tree waits on the Eorzean clock.

Dwarven Cotton is itself consumed by 165 further recipes, spanning eight of the eight crafting classes.