Elder Stone

Description
A luminescent, highly radioactive alien material. When a player is standing on this block, it confers the "Radiation Sickness" debuff, which causes 5 damage per tick.

Location
It can be found on alien, jungle, scorched, toxic, volcanic, Unknown (lowest chance since it has greatest variety), superdense, strange sea, shadow, primeval(dark), atropus, irradiated, chromatic, bloodstone, and tropical planets with radiation. It can only be found in its unique biome.

Uses
It can be used with a Prisilite Star to create Alien Compound.