Finding Clay and Fossils in Underground Biomes

Clay blocks

Each stone family has a clay block: Andesite Clay, Basalt Clay, and Black Granite Clay. These generate inside their matching regions underground. Dig through an Andesite area and you may uncover Andesite Clay; the same applies to Basalt Clay in Basalt regions and Black Granite Clay in Black Granite regions. Mine them with any tool and they drop the block.

Ammonite Fossil

Ammonite Fossil is the fossil block found in these underground regions. It appears as a distinct block embedded in the surrounding stone. Mine it when you spot it and keep it for decorative or crafting use.

Working the clay

Once you have Andesite Clay, Basalt Clay, or Black Granite Clay, treat it like a building and crafting material. Use it as a textured accent against the plain stone, cobblestone, and brick shapes of the same family — for example, Andesite Clay next to Andesite Bricks, Andesite Brick Slab, Andesite Brick Stairs, and Andesite Brick Wall. The same pairing works for Basalt Clay with Basalt Bricks and Black Granite Clay with Black Granite Bricks. Because clay blocks are soft, they break quickly, so you can strip a vein without slowing your tunnel. Carry a few stacks back to your base and store them separately from your stone so you can grab them when a build calls for a smoother surface.