Armor that is currently worn by the player cannot be detected by the recipe book. This includes gold, iron, and chainmail armor (all of which can be smelted into their respective material nuggets).
Steps to Reproduce:
Equip either gold, iron, or chainmail armor
Give the player all recipes:
/recipe give @p *
Open the recipe book inside a furnace, or blast furnace
Turn to the 'ores' tab
Observed & Expected Results:
❌ - All recipes will be impossible to complete, despite having the required items to complete them.
✔ - As the player currently has one of the applicable items inside their inventory, it would be expected that the recipe would be possible to auto-complete.
Screenshots/Videos:
[media]
Notes:
This issue is (partially) blocked by MC-207201
Linked issues
relates to 3
Attachments
Comments 2


Thank you for your report!
After consideration, the issue is being closed as Working as Intended.
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I'd expect this to be intended. My reasoning is you wouldn't want to accidentaly unequip your armor when clicking a recipe, since, well, it's gear, and most of the time you won't scrap away your valuable (un)enchanted gear.
Also, gear slots not being exposed in the furnace GUI is another factor that contributes to what i've said.