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.

Blacksmithing: Weapon Stones
RecipeMakesReagentsNeedsSkill-up
Rough Sharpening Stone
Rough Sharpening StoneYellow 15Grey 55
Rough Weightstone
Rough WeightstoneYellow 15Grey 55
Coarse Sharpening Stone
Coarse Sharpening StoneYellow 40Grey 55
Coarse Weightstone
Coarse WeightstoneYellow 40Grey 55
Heavy Sharpening Stone
Heavy Sharpening StoneYellow 100Grey 115
Heavy Weightstone
Heavy WeightstoneYellow 100Grey 115
Solid Sharpening Stone
Solid Sharpening StoneYellow 175Grey 185
Solid Weightstone
Solid WeightstoneYellow 175Grey 185
Dense Sharpening Stone
Dense Sharpening StoneYellow 230Grey 235
Dense Weightstone
Dense WeightstoneYellow 230Grey 235
Elemental Sharpening StoneTaught by Plans: Elemental Sharpening Stone, requires 300
Elemental Sharpening StoneYellow 275Grey 295

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