Meteorite

Meteorite is mined from meteorite crash sites (which can be caused by breaking a Shadow Orb), and requires a Gold Pickaxe or better. It also has 2% chance of being dropped by a Meteor Head.

Once fallen, Meteorite can be located in nearly any area in the world map, even underwater and on the floating islands. A message will appear telling you that it has landed. A meteor can even land near or on NPC settlements. Four Meteorite ores are required to make a Meteorite Bar.

Contact with Meteorite blocks causes damage, unless the player has the Obsidian Skull equipped, or is using the Obsidian Skin Potion. Meteorite can be mined without these defenses, so long as the player doesn't come into contact with the blocks except through use of the Pickaxe. The ore is safe to collect once mined.

Any area with 50 Meteorite blocks in close proximity becomes a Meteorite Biome, including the natural crash site, which will spawn Meteor Heads until fewer than 50 Meteorite blocks are present.

Mining methods

 * Players lacking an Obsidian Skull or an Obsidian Skin Potion can coat the meteorite in a layer of sand, then mine the Meteorite underneath.
 * Use Dynamite, Bombs, or Sticky Bombs. This can stop the spawning of Meteor Heads more quickly.
 * Equip a Cobalt Shield and let the Meteor Heads hit you, and only defend yourself long enough to heal when needed.
 * The Pickaxe can be repositioned strategically while mining to continually knock back Meteor Heads.
 * The Vilethorn kills a Meteor Head in one strike. The Vilethorn is particularly useful to deal with Meteor Heads at long range and before they've breached the surface where they could be hit by other weapons. By alternating between grabbing a couple pieces of meteorite and clearing out the approaching Meteor Heads the entire meteor can be cleared efficiently and safely, if not necessarily quickly.
 * Trap six enemies (Zombies are the easiest) so no Meteor Heads can spawn, letting you mine in safety. Make sure that you keep the six enemies on screen at all times, or they could de-spawn, letting Meteor Heads spawn. This method lets you mine even if you only have low-level armor, and lets you use useful equipment (such as Rocket Boots) instead of having to use battle equipment. It may take a while to trap the six enemies, but overall it can make meteorite mining a lot quicker and easier.

Artificial Meteor biome
If the Player places at least 50 pieces of Meteorite on the screen, they can create an artificial Meteorite Biome. In the Meteorite biome, all monster spawns are replaced by Meteor Heads, which can be more predictable, and tend to do less damage, than the naturally-spawning creatures of The Underworld. If the Player can withstand the Meteor Head attacks they can mine Hellstone in relative peace. Also, in Hardmode, Meteor Heads still spawn Souls in Underground Corruption or Underground Hallow.

Meteorite cannot replace the Ocean biome, ie. if a Meteorite falls into Ocean, there will still be Sharks and Crabs, with very few Meteor Heads. A Meteorite will also not override the spawns of a Goblin Invasion or Harpies.

History
Météorite Метеорит