Lava Still
Official Minecraft Wiki Entry
Lava Still
Type Fluid
Physics Partially
Transparency Yes
Luminance 15
Blast Resistance 0 (Flowing)
500 (Still)
Tool Grid Bucket
Renewable No
Stackable Lava64
Flammable No
Fluid Movement Speed 1/30 m/tick
Speed Walking Through Very Slow
Appears in Minecraft
First Appearance Classic 0.0.12a
Block Data Information
Decimal Data Value 11
Hexadecimal Data Value B
Binary Data Value 1011

The Lava Still fluid must edited into the player's inventory, as only Lava Source blocks can be placed with Buckets. Once placed, it starts to replicate with additional Lava Still blocks after a short while, until it reaches ground.