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Hardened clay can be mined using any pickaxe. If mined without a pickaxe, it will be destroyed.
Hardened clay can be found naturally in mesa biomes. This yields a large quantity of hardened clay.
Hardened clay blocks can be obtained by smelting a clay block in a furnace .
Hardened Clay can be dyed similar to wool and leather using 8 block surrounding any dye.
Hardened clay has the same explosion resistance as most other stone blocks, which is significantly higher than a regular block of clay before being smelted. A block of hardened clay when one meter away from an explosion will protect any blocks behind it, though it will be destroyed in the process.