Powdered charcoal

item game:powder-charcoal · from betterruins

Used in (2)

Filters

Recipe	Category	Ingredients → output
Terra preta (Item Recipe)	grid	Compost + Powdered charcoal ×2 + Bonemeal ×2 + Farmer's Blueprint → Terra preta
Terra preta (Item Recipe)	grid	Compost ×2 + High fertility soil + Powdered charcoal ×2 + Bonemeal ×8 + Farmer's Blueprint → Terra preta ×3

Found in structures (4)

Structure	Kind
Village area	storystructure
university	storystructure
megastructures-palaceofnestor-nybygget	structure
village-forest	village

This confirms the schematic(s) contain this code somewhere, not where or how many times -- the per-instance block-entity decoding used for tapestries isn't run for every content type.