Always Be Prepaired
Location
Required Items
Rewards
What the allowance actually buys
One allowance here buys 2,695,430 EXP, the best of the 2 Lv 90 Blacksmith tradecraft leves that record EXP: the runner-up manages 1,858,920 EXP, 31% less.
On whether to wait: the best Lv 92 Blacksmith tradecraft leve returns 3,115,640 EXP per allowance, 16% more than the best on this rung, while the Lv 88 rung behind tops out at 2,297,800 EXP.
At Lv 90 this data holds 18 leves paying EXP across 2 categories: the 16 Tradecraft ones average 1,797,551 EXP per allowance, the 2 Fieldcraft ones 4,395,018 EXP, which puts this leve 50% above its own category's average.
Mountain Chromite Twinfangs ×1 is a Lv 91 Blacksmith recipe, 3 steps deep through 4 intermediates, costing 35 units of raw material and 71 crystals.
Handing that in returns 77,012 EXP and 145 gil for every unit of raw material the order swallows, and the tree needs Blacksmith and Goldsmith.