Arlemite Ore

Arlemite Ore is a mineral block found underground in the overworld. Smelting Arlemite Ore will produce Arlemite Ingots, which are then used to craft a variety of items. To obtain Arlemite Ore, the player must mine it with an Iron Pickaxe or better. Arlemite is considered to be a medium tier ore in the Overworld - it's better than Realmite, but is weaker then Rupee.

Natural Occurence
Arlemite Ore occurs only at Y=15 or lower. There are about 4 Arlemite Ores per chunk. Arlemite veins come in 1 to 3 ores, making it extremely rare and difficult to find.

Mining
In each chunk, there will always be 2 veins of Arlemite. In each vein, there can be 1-3 Arlemite Ores. Therefore, if you require Arlemite, mining out an entire chunk from levels 15 to 6 will always yield a minimum of 2 Arlemite Ore. Arlemite Ore can also be found in a niche of Bedrock, so it might be worthwhile to mine down past the upper bedrock levels. Strip Mining is also an effective techniques to acquire Arlemite Ore.

Uses
Arlemite Ingots can be used to make various tools and weapons. However, it is not recommended to make them because the slightly more common Rupee is a higher tier ore. Arlemite's main use is in the creation of Shadow Bars, which have many other crafting uses.

Arlemite Armor is quite powerful because the full set offers a 80% damage reduction against ranged attacks.

Trivia

 * Arlemite Ore is strangely more rare than Rupee, even though Rupee is a higher-tier ore.
 * Similarly, Arlemite Ore must be mined with an Iron Pickaxe or better, while Rupee can be mined with a Wooden Pickaxe.
 * Oddly, Arlemite Ore cannot be blown up using TNT