Lava Bucket

Lava Buckets are buckets of lava. They are formed when you tap Lava with a Bucket. Lava Buckets are used to carry lava from place to place. They can also be used in a furnace to get upto 100 smelts.

Trivia

 * Some Players use lava buckets as a weapon- they carry a lava bucket and quickly place it down if a hostile mob is chasing them, burning the mob. Note that this method does not allow you to collect the mob drops. Also, any surrounding wooden structures may also burn down.
 * Lava, like water, can only be collected from buckets through the source block.