Tempered Glass ★★

Taken all the way down to base materials, one Tempered Glass is 2 crafting steps deep and needs 1 intermediate — Natron ×1 — which resolves to 5 distinct raw materials totalling 7 units, plus 16 crystals.

That bill outweighs 4,963 of the 13,602 recipes tracked here and 980 of the 1,591 Alchemist ones, and 4,464 recipes nest deeper.

Only 14 of those crystals go into the final step; the other 2 are burned by the intermediates, so the real crystal cost is 7 Lightning Crystal, 7 Water Crystal and 2 Water Shard.

Every step is Alchemist work, from a Lv 25 intermediate up to the Lv 60 finish, so one class covers the whole chain.

3 of the 5 raw materials match a gathering node, none of them timed; the other 2 come from vendors, drops or content this site does not track.

Tempered Glass is itself consumed by 6 further recipes, spanning three of the eight crafting classes.