Minecraft resource gathering/Redstone

You can find Redstone underground at y-level 32 or below. You must mine it with an Iron-tier or higher pickaxe or it will not drop anything. It will drop 4-8 Redstone Dust, which can be used for redstone cirucits.

Witches also drop up to six peices redstone Dust.

Redstone Dust can be used on a brewing stand with most potions to make the potion last longer.