Deepgold Uchigatana

Taken all the way down to base materials, one Deepgold Uchigatana is 2 crafting steps deep and needs 4 intermediates — Deepgold Ingot ×3, Cobalt Ingot ×1, Hard Mudstone Whetstone ×1 and 1 other — which resolve to 6 distinct raw materials totalling 26 units, plus 47 crystals.

That bill outweighs 9,543 of the 13,602 recipes tracked here and 1,087 of the 1,932 Blacksmith ones, and 4,464 recipes nest deeper.

Only 12 of those crystals go into the final step; the other 35 are burned by the intermediates, so the real crystal cost is 24 Fire Crystal, 12 Wind Crystal, 6 Earth Crystal and 1 other kind.

The chain crosses two disciplines — Blacksmith to Lv 72 and Goldsmith to Lv 72 — so no single class can finish it unaided.

All 6 raw materials are gathered, and one of them is time-gated: Gold Ore (9:00). That window comes round once per Eorzean day, every 70 real-world minutes.

Of the intermediates, Cobalt Ingot has the widest use: 145 recipes call for it, spanning seven of the eight crafting classes.