Ores

Ores are primary crafting materials necessary for game progress. They generally must be crafted into bars at a Furnace, after which they can craft several essential tools, weapons, armor, and other items. Some items require raw Ores themselves, most commonly bricks and potions. Raw Ores can also be used as plain blocks for construction.

Ores are generally found as veins of placed blocks Underground and below, and are mined with a Pickaxe. Lower-tier Ores can be found among Dirt near the Surface, or within Floating Islands. Some Ores are also dropped by bosses, namely Eye of Cthulhu, Eater of Worlds, Brain of Cthulhu,, and.

An Extractinator, or Wooden Crates (from Fishing), may also provide Ores as random rewards.

A world will generally only contain one Ore type from each tier, which are chosen at random (see tables below). The alternate Ore types that don't generate naturally in a world can be obtained from Slimes, Crates, an Extractinator, or from other worlds. Hardmode Ore types are chosen at random when players destroy Altars.

Hardmode
Spawning the first three tiers of Hardmode Ore requires the destruction of Demon/Crimson Altars. This requires a Hammer with 80% hammer power or higher, e.g. the Pwnhammer. Each destroyed Altar spawns deposits of one of six new Hardmode Ores, replacing natural world blocks below the underground layer:


 * 1) First Altar: Cobalt Ore or Palladium Ore
 * 2) Second Altar: Mythril Ore or Orichalcum Ore
 * 3) Third Altar: Adamantite Ore or Titanium Ore


 * Destroying a fourth Altar spawns another round of whichever type spawned for the first Altar (Cobalt or Palladium). A fifth spawns more of whichever type spawned for the second Altar (Mythril or Orichalcum), etc.
 * Destroying more Altars will never spawn Hardmode ore types beyond the 3 that were randomly assigned to your world during the initial round of destroyed Altars. A world with Palladium Ore deposits will never spawn Cobalt Ore deposits, or vice-versa.
 * Ore spawns will never overwrite existing mineral deposits or placed Wood blocks of any type, nor any form of Brick, only natural biome blocks (such as Dirt, Mud, Stone, etc).

Chlorophyte Ore spawns on its own once Hardmode is triggered, and Luminite does not occur naturally. Neither are affected by destroyed Altars.

Tips

 * Each Hardmode ore is chosen at the moment you break the first three Altars in the world. You can choose the ores you like by quitting your world without saving (by ending the task or killing the process) after smashing your first Altars. It is more easily done with a server, using the  command.
 * All ores except Hellstone and Obsidian are highlighted by the Spelunker buff, making it easy to find veins of ore. Hellstone is not lit up by the buff, but it is by a Dangersense Potion. Obsidian is easily found and made around lava.
 * Using a Crate Potion will improve the chances of obtaining crates, and as such the ore-bearing Wooden Crates.
 * If you fill in caves with spare natural blocks such as dirt, then destroy Altars, Hardmode ores can spawn in them. They can then also be seen on the minimap, presenting an easy way to convert extra blocks into ores and know their exact location.
 * In the, the Palladium Pickaxe and drill can mine Adamantite and Titanium.
 * Most ores sell for the same as or more than the bars made from them. The exceptions are the late pre-Hardmode ores (Meteorite, Demonite/Crimtane, Hellstone), and Chlorophyte, all of which are far more profitable as bars. (Hellstone and Obsidian are unsaleable as ores, and there is no Obsidian Bar).
 * There are a total of 20 types of ores in Terraria in the current update 1.3.5.3.

Trivia

 * Hellstone's item sprite is a recolor of that of Silver Ore.
 * Hellstone and Chlorophyte are the only ores that cannot be infinitely generated within a single world. Others can be obtained from sources such as Crates, an Extractinator, bosses, duplicable Liquids, and Meteorite crashes. Furthermore, Chlorophyte can be grown using mud, which, while not truly infinite, is unlimited for all practical purposes.
 * Iron and Lead are the only ores not to have bricks.
 * Despite being a late-game ore, Chlorophyte Ore only sells for per ore. This may be because the player can keep farming large amounts of Chlorophyte Ore and selling it for money. Luminite sells for the most, being  per ore.
 * Palladium, Cobalt, and Titanium are the only Hardmode ores named after real metals.

History
Erze Minéraux 광석 Rudy Ores Руда 矿石