Short answer
Explosive Dust is brewed from ingredients whose runes total exactly 2 red and 2 blue, and the formula unlocks with the Dynamite technology. Laboratory I is enough: Night flower + Red Mushroom or Tin + Blueberry both work. Two free units sit in a Simple Chest in the Old Mine. Its only use is Dynamite — 2 Explosive Dust + 1 Alcohol at the Formulation Bench.

The Astrologer's Tower
View full-size image ↗Official promotional screenshot · © Lazy Bear Games / tinyBuild · Official media kit · Material credits
The rune formula
Target: 2 red, 2 blue. It is one of the easier formulas, with dozens of two-ingredient mixes.
Mixes listed by wikily.gg: Night flower + Red Mushroom, Tin + Blueberry, Minced Meat + Red Mushroom and Clay + Heart (Gold). Blueberry + Blueberry + Red Mushroom works in a three-slot lab.
Each brew costs 1 Alchemy Flask.
The free dust
A Simple Chest inside the Old Mine holds 2 Explosive Dust at the start of the game. It fills once and does not restock.
You only reach it after the mine entrance is cleared — the quest Can't See The Forest for the Iron hands you the first Dynamite for that.
Making Dynamite
Dynamite is 2 Explosive Dust + 1 Alcohol at the Formulation Bench, taking 8 ticks at 2 energy per tick, after the Dynamite technology.
Alcohol comes from the Distillation Cube, which has its own gate — see our alcohol guide.
In The Town, Dynamite is used for the Demolish the Wall restoration project and the Broken Wall repair.
Original diagram: Dynamite clears the Old Mine entrance, where the free Explosive Dust chest sits.
View full-size image ↗Original diagram · Graveyard Keeper 2 Wiki · editorial illustration · Original wiki diagram
Don't try to sell it
No trader buys Explosive Dust or Dynamite.
Patch 1.007 closed a Dynamite destroy-and-sell exploit, so brew only what your projects need.
Sources
- communitywikily.gg — Explosive Dust
- communitywikily.gg — Explosive Dust formula
- communitywikily.gg — Dynamite
- officialSteam — Changelog 1.007
Related pages
Official screenshot · © Lazy Bear Games / tinyBuildCraftingGraveyard Keeper 2 Mine: Old Mine, Dynamite & Zombie Miners
Official screenshot · © Lazy Bear Games / tinyBuildAutomationHow to Make Alcohol in Graveyard Keeper 2
Official screenshot · © Lazy Bear Games / tinyBuildCraftingGraveyard Keeper 2 Formulation Bench
Official screenshot · © Lazy Bear Games / tinyBuildAutomationGraveyard Keeper 2 Alchemy Guide
Official screenshot · © Lazy Bear Games / tinyBuildCraftingGraveyard Keeper 2 Coal