Redstone Ore

 For the advanced Redstone circuitry, see Redstone circuits. Redstone ore is the form that Redstone takes when generated in a map. Redstone is a fictional mineral with magnetic and conductive properties, as it is used in all circuitry and compasses. Redstone Ore is, most commonly found within 10 blocks of Bedrock.

Redstone ore drops 4 - 5 piles of Redstone Dust when mined with an Iron Pickaxe or better. Redstone ore forms in veins made up of 1 - 10 blocks. This makes it relatively easy to obtain large amounts of Redstone.

If a player left or right clicks on, or an Entity moves or falls on Redstone ore, the block will emit level 9 light until it receives the next block tick (47 seconds on average).

Redstone ore veins form at the bottom 16 layers of the map. Below layer 14, it can be found in 1.025% of stone. There are an average of 25 redstone ores per chunk.

Redstone ore can be obtained by the enchantment Silk Touch on a pickaxe. You can then use the redstone ore block to create traps or even decoration.

Smelting
Note that the Redstone Ore block can only be obtained with a pickaxe enchanted with Silk Touch. Also, smelting the ore instead of mining it is highly inefficient, as mining the ore block yields 4-5 redstone dust rather than the single dust that smelting yields.

Power
Coming in contact with Redstone Ore or hitting it will cause it to emit the same amount of light as a redstone torch as well as red particles for a few seconds. Redstone ore can also become powered by a mob in contact with it. This can be used as a substitute for pressure plates, when combined with a block update detector, as it can be used also on a wall or a ceiling. However, the ore can be hard to blend in as a trap as it does not blend in with some building materials such as wooden planks, bricks, or cobblestone. Redstone ore also does not power if the player sneaks while standing on it, which can ruin traps.

History
The block was added on Alpha version 1.0.1 in Seecret Friday Update 3 on July 3, 2010.

Before 1.9 Prerelease 6, Redstone Ore took far longer to mine compared to other ores (4.5 seconds with iron pickaxe). As of 1.9 Prerelease 6, it now has the same mining time as other ores.

Trivia

 * When added to the game, all Redstone related blocks had no official name. In Alpha 1.0.4, July 9, 2010, the name Redstone was given by Notch after demands from the community.
 * With the Silk Touch enchantment, this ore can be collected as an item. It can be smelted into a single Redstone Dust, but it is much more useful for decoration, especially for its unique glowing trait.
 * The block updates when stepped on, making it useful for traps and secret entrances. The block is also updated whenever the player either hits or right-clicks the block.
 * Coal is more common as an ore when mining, but technically, redstone is more plentiful since when deep enough, it's as common as iron, and yields 4-5 redstone dust for every ore.
 * Like all ores, Redstone Ore is fairly evenly distributed horizontally. It is not more common near lava pools but may appear more common near deep lava pools because more blocks are pre-exposed by the world generator boring out the cave.
 * Redstone Ore, along with Diamond Ore and Gold Ore, can be found in Pocket Edition but have no use and are currently (as of 2012/07/16) unobtainable even with a diamond pickaxe.
 * Redstone Ore and Coal Ore are the only ore blocks that do not have their own mineral blocks
 * In Minecraft 1.3, mining Redstone Ore, along with other ores, gives you experience orbs, allowing for a different way to get enchantments. One stack of Redstone Ore will give roughly 10 lvl.