Each recipe is orange until its yellow rank and grey from its grey rank. When the ranks differ, it turns green somewhere between the two; the client files give both ranks but not that point. Equal ranks go straight to grey.

Leatherworking: Ammo Pouches
RecipeMakesReagentsNeedsSkill-up
Small Leather Ammo Pouch
Small Leather Ammo PouchYellow 55Grey 85
Heavy Leather Ammo Pouch
Heavy Leather Ammo PouchYellow 145Grey 165
Thick Leather Ammo Pouch
Thick Leather Ammo PouchYellow 220Grey 240

From the Forever beta client files, build 1.60.1.70630: the SkillLine, SkillLineAbility, TradeSkillCategory, SpellReagents, SpellEffect, SpellTotems, SpellCastingRequirements and ItemEffect tables.