Hardmode Ores are generated upon destroying a Demon Altar or Crimson Altar with a Pwnhammer. They are immune to all types of explosions. You need at least a Molten Pickaxe to mine it.
Palladium Ore spawns in place of Cobalt in some worlds.
A player finding some Cobalt Ore
- On a small map Cobalt ore spawns below a depth of 710 feet (355 tiles).
- On a medium map Cobalt ore spawns below a depth of 1,100 feet (550 tiles).
- On a large map Cobalt ore spawns below a depth of 1,270 feet (635 tiles).
Sometimes doesn't spawn on Xbox360.
- Actual Cobalt is a poisonous, magnetic metal (though it is actually a key part of vitamin B12, which is necessary for living beings and has extremely low toxicity).
- Cobalt is named after the Kobold, at that time thought of as a mischievous spirit.
- Pure cobalt is an element found on the periodic table just after iron, and is actually silver-like in color. However, cobalt is never found pure in nature. Its historic primary use was as a pigment used especially in glass or porcelain, as it turns a rich "cobalt blue" when in the compound form of Smaltite, made of cobalt, iron, and nickel combined with Arsenic. This made cobalt, along with lapis lazuli, one of the few mineral blue pigments, and therefore was historically an extremely valuable commodity.
- Several Cobalt items in the game are Japanese-themed, namely the Cobalt Naginata, Cobalt Armor and the Cobalt Sword which resembles a katana.
- 1.2.3: Increased stack limit from 99 to 999.
- 1.1: Introduced.