Lava is a terrain resource found deep underground in Sandustry. It is a key input for both the gold chain (as the heat source for the Slag Burner) and the thermal/energy system (as a source of steam).
Where to find lava
Lava generates naturally in Lava Caves deep underground. You will not find it on the surface — you have to dig down to reach it.
How to move lava
Lava is a fluid, so hauling it by hand is slow and dangerous. The practical way to move it is to change its state first:
- Freeze it with a Cryoblaster. Frozen lava becomes cinder (some sources call the frozen form scoria), which is a solid you can transport safely.
- Re-ignite it where you need it. The cinder can be lit again once it is in position.
The official wiki describes a neat trick for holding lava anywhere: set a Filter to only allow Cinder, place a solid block underneath, fill it with cinders and ignite them. The Filter now holds lava wherever you put it, with no piping needed.
What lava is used for
- Burn slag — the Slag Burner uses lava's heat to roast slag into burnt slag (see the slag burner page).
- Make steam — when water lands on lava, the water evaporates into steam, and the lava does not decrease. This makes lava a cheap, reusable heat source for the Boiler and thermal chain.
- Automate burners — lava can be trapped inside a Filter, and any pixel that passes over it ignites if it can burn. That is the standard way to build automatic Residue and Flower burners in a factory.
Lava in the gold chain
Lava is the heat source upstream of the gold production line:
Lava (heat) → Slag Burner → Burnt Slag → Kinetic Slag Press → Gold + Seed
So while lava is not itself turned into gold, a reliable lava supply is what keeps the burn stage of the chain running.
See the boiler page for how lava's heat drives steam production.
The other major use is the Slag Burner, where lava provides the heat needed to process slag.