The first backpack tier is fine it requires [Copper] that the profession can refine.
The issue is the 2nd 3rd and 4th Tiers…
[Sturdy Jeweler’s Tools] for [Sturdy Jeweler’s Backpack (Master)] …needs [Iron Ingot]
[Practical Jeweler’s Tools] for [Practical Jeweler’s Backpack (Rare)] …needs [Steel Ingot]
[Intricate Jeweler’s Tools] for [Intricate Jeweler’s Backpack (Rare)] …needs [Darksteel ingot]
Tier 2/3/4 Backpacks require materials that the Jeweler Profession does not refine.
Huntsman, Leatherwork, Blacksmith, Weaponsmith do not share this problem.
In Cooking you craft the tools with FOOD instead of METALS.
2 Suggestions:
-Use Tier 2/3/4 Gems in place of Iron/Steel/Darksteel
-Use Silver/Gold/Platinum in place of Iron/Steel/Darksteel