Oil of fire stilling

Oil of fire stilling was a type of magical oil that, when applied to wood, gave it resistance to fire. When any wooden structure that had been treated with oil was struck with flame, it would not be able to spread. This protection could last up to five tendays, but left the wood rather dried out.

Usage
This type of oil was particularly popular with spelljamming ships that sailed the Flow, a particularly flammable region of wildspace.