Redstone is an item in Minecraft. It is dropped from Redstone Ore or from trading with villager priests. This item is for carrying redstone signals between blocks. Redstone takes the form of a red powder and can be used in brewing as well. A redstone signal will only travel for 15 blocks before losing it power completely.
In brewing, is used to extend the time a potion provides an effect. This is useful if a player wants to undergo longer expeditions (such as an Extended Potion of Night Vision for exploring a deep cave instead of a normal one, or a long swim across a lava lake in the Nether with an extended Potion of Fire Resistance).